If your game freezes and/or subsequentially crashes during a loading screen then the problem is with an incompatibility between the fullscreen and the color depth of the game.
So, open the game main folder which is at
or alternatively right click on Sacred Gold in your Steam Library, click Property click on the Local Files tab and click on Browse Local Files... .
Then open the Config.exe file and either disable the Fullscreen option (which will render the game in a fixed 1024x768 borderless windowed mode)

(this seems like a poor fix but forward in this guide I'll explain how you can play it windowed mode in a much cleaner way you're seeing right now) or alternatively you could enable the 32bit Color Depth (this way you can immediately start playing, even in fullscreen).
If the game still crashes or is displayed in the wrong settings, check the Config.exe file again to see if the game didn't revert the settings back to default (sometime, especially the first times, it happens for no reason).

There are a couple of in-game options that could seriously tackle your experience with the game.
The first one is the "Graphic Details" that you can find in the Options menu of the game.

The "Low" setting disables ALL shadows from background/interactable objects while keeping a generic round and undefined shadow for entities, it gives a solid amount of fps, with the drawback looking at a very shallow game.
"Medium" renders a well defined shadow for all entities and background/interactable objects, it takes away a good amount of fps but makes you see the game for what it was intended to be.
I have no idea what's the purpose "High", all the areas I tested it in, weren't graphically dissimilar from "Medium" and the fps were about the same (which means there were no changes there).
Either it does nothing or it does something so little I didn't even notice it was there in the first place (let me know with a reply and I'll test it further) (p.s. looking at it a second time, it seems it smoothes the edges of the shadows a little bit).

The next two do not affect fps but could hinder the playability nonetheless.
The first one is "Sound", it can either be "2D Low effects" or "2D All effects".
"All effects" let's you hear all the sounds the game has intended to let you hear, while "Low effects" disables all monsters sounds, including your own summons and companions, basically the only sounds left are: the music in the background, the voiceover of the character and few talking NPCs and a couple of muffled SFX.
It doesn't reduce your fps whatsoever so you might as well keep "All effects" enabled.
Don't know what a 3D sound card does because I don't have one.

Next is FSAA Filter (which is a kind of Anti-Aliasing filter, which renders, especially the borders, of entities in a non-segmented way so they end up looking much better in the distance, at the expenses of some fps drawback).

Being a top-down 2D game with a fixed background I don't know what purpose it could serve, but if enabled, not only it does not impact fps in any way, neither positively nor negatively, but what it does is breaking down the textures of both the background and interactable objects in a really ugly way, sometimes crunching up objects (especially noticeable when rapidly switching between the pictures in an editor, leaving the impression that they sectioned the image in squares and re-arranged the pixels by approximating them near the center of these "squares") or leaving mismatching streaks where the textures should line up, overall giving the game screen a blurred feeling (you can see it on the grey rocks in the bottom left corner of the image).
Leave it disable for the intended game experience.

Do NOT complete the quest named The Riddle in the Desert, located in Oasis of Ahil-Tar, before you have thoroughly completed the following quests:

• Where is the Blacksmith? located in Bellevue
  
• Whispers in the Wind, in the town of Florentina
  
• The Unknown Warrior in Tyr-Fasul and Braverock Castle, but only its last two parts are bugged
  
• and The Painting in Mascarell

some of these you outright won't be able to start them, others you won't be able to complete them and will remain unmarked in your log.

Do NOT enter any underground cave/dungeon/crypt where there is/are locked door/s that will later be opened by a key item given by a quest, as they will otherwise be locked forever, even after you have retrieved their respective key.
Namely, but probably not exhaustively, the following quests will be broken to certain degrees or outright unsolvable:

• Buried Slaves located in Zhurag-Nar won't actually be unsovable but it will require talking to the Slave Leader through the gates he's in and take advantage of his NPC teleporting abilities
  
• The Spider Monster of Moorbrook located south of Moorbrook will however be unsolvable, as you won't be able to traverse the first door right at the entrance of the dungeon that's right under the start of the quest
  
• The dungeon of the quest Scroll of Mhic 'Dar-Mon is located to the left of Khorad-Nur and if you enter it before taking the quest located in Khorad-Nur you won't be able to traverse the final door and get the key item behind it in order to solve the quest

Do NOT traverse teleporters that lead to underground maps while mounted on a horse; they can't physically be in them and the game doesn't dismount you automatically, which means that it will activate regardless but you won't be teleported, which means that if it was a one-time chance, you've lost it and have to load a previous save.
One of them being the teleporter located at the base of the statue of the Forest God near the end of the quest called HRunga'zz in the town of Gloomoor.

If you experience low fps and/or stutters, especially when zoomed out, an easy and quick fix, which will help you gain a substantial amount of fps, is to disable the forced by default Vsync, by adding the line
to the file Settings.cfg in the game's main folder (that you can find by following the instructions above mentioned).

(you can safely write the line at the end of the file, but once it gets recognized by Sacred it will put it in alphabetical order, which is why you see it just above the "WARNING_LEVEL : 25" line)
Mind you, Vsync is supposed to help vertically syncing the game with your monitor's refresh rate.
If disabled AND in fullscreen, it could therefore result in horizontal lines appearing on your monitor while you're playing (fortunately I've never seen this glitch appearing but if you do encounter it and you want to fix it, either enable Vsync again by removing the line or switch to windowed mode)
(again, I'll explain further on in this guide, how to play on it properly without partially blocking the game with your Applications Bar and showing a distracting portion of your desktop active).

Either because you frequently alt-tab out of the game and it ends up crashing (be careful though if you're used to fullscreen, as windowed mode doesn't have problems when going outside the game, because it actually doesn't; no matter where you are, the game keeps running in the background, so if you're not careful and forgot to open up a menu that pauses the game you might get killed in the game while you're doing something else on another window) or because you want to gain some fps by going windowed mode (in certain areas it ends up almost doubling your fps) and/or take advantage of this mode in order to safely disable Vsync (as there's no need for it when not in fullscreen), you might want to consider playing windowed mode.
If you decide so, you can also disable the 32bit Color Depth option above mentioned in this guide, as there will be no incompatibility between this and fullscreen anymore and therefore no need for it to be enable. Further on it will however be enabled nonetheless by another application (Res-o-matic), combined with the fact that it doesn't impact your fps in the slightest, it really makes no difference if you keep the 32bit Color Depth option enabled or not, I usually disable it just to be safe.

Another important note: in order to pull this fix, you will have to create a shortcut and access the game from it and no longer from Steam (this WILL hinder your ability to interact with Steam in some way, as you'll lose access to the Steam Overlay, which is the one responsible for making you able to browse Steam and its Web Browser by pressing Shift-Tab, or whatever keys you binded the Steam Overlay to, while you're playing; you also won't be able to take screenshots with Steam, but you can still take them with Sacred by pressing Ctrl+B, which you can find them in the Capture folder inside the game's main folder, already mentioned above in this guide how you can find it; you also won't be able to visualize your game's fps if you enabled them nor see the Steam popup in the bottom right corner as you open the game, and many other features).

First of all, you might want to know that the game is hard-coded in the resolution 1024x768 so there's not a real way of stretching the image to your (presumably) larger screen resolution.
If your screen's resolution is equal or lower than 1024x768 you can safely play in windowed mode by disabling the Fullscreen option in the Settings.cfg file in your game's main folder (that you can find using the aforementioned method)
The fix consists instead of changing your screen resolution around the game, without having the hassle to mess with your Windows options everytime you wanna open or close the game.

So, download the program Res-o-matic by bCheck[www.bcheck.net](you might want to just download the exe if you don't know what you're doing). Before you do anything to it, give it a proper place within your data system because, since the shortcuts will need to access the .exe, if you'll ever decide to move it or delete it, the shortcuts will no longer work and you're gonna have to create them again.
Now open the .exe

click Browse and select the game's main folder, which is once again located at
Then select the resolution 1024x768, set the color depth as high as your computer allows and the refresh rate exactly as is your monitor's (you can easily check, in Windows 10, your monitor's refresh rate by right clicking on your Desktop, selecting Display Settings, scrolling all the way down and selecting Advanced Display Settings,

your monitor's refresh rate should be displayed in Hertz right under your resolution) (your monitor refresh rate simply indicates the frequency at which the monitor refreshes the screen with a new image every second, so if your monitor is at 60Hz (like 99% of them are) and you played a video or a game at 120fps you would only be able to see it at 60fps, maybe with some graphical glitches along the way, BUT with the hinderance on the performance of a 60fps video/game, much like a funnel that gets clogged up by the amount of informations that are coming, so always check that the fps of what you're playing, match your monitor's Hzs).
Once you've done all of this, click Create Shortcut and save the shortcut wherever it's easier for you to access the game, with whichever name you want to give it.
You can now close the application and remember to not delete or move the .exe.

If you want to access the game from now on you, remember to open it with the shortcut, NOT from Steam, as you'll just access the game in its default windowed mode (with the application bar covering the game and half the screen taken by your Desktop instead of two neet black bars).
Also, don't open the shortcut if Steam is closed, because it needs Steam open anyway for a game to work so what'll happen is that the screen will change resolution to 1024x768 and back to normal (indicating that Res-o-matic first thought the game was starting, but then saw that it didn't immediately open and reverted the resolution back), then Steam slowly starts and checks for updates, then finally the game starts but in its default windowed mode, making this fix completely useless and having to close and re-open the game.

If you're still having issues with the framerate you might want to use dgVoodoo, a wrapper commonly used with old games, that lets you force certain options on a specific game that you wouldn't normally have access to.
Download the latest version of dgVoodoo[www.dege.freeweb.hu](by clicking on the first link after the line "Latest stable version") and extract all the .zip's contents (the password is "♥♥♥♥♥♥♥♥♥♥" eheh).
Now take all the .dll files (should be 4) in the folder MS\x86 and drop them in the game's main folder (which you can again find with the above mentioned methods).
Now open the dgVoodooCpl.exe file to access the program's options.

In the top, click the Add button and select the game's main folder. This will make it so the options that you're gonna edit next, are gonna create/change a "dgVoodoo.conf" file in Sacred's main folder that's gonna configure the game above its vanilla options.

You NEED to change the folder in the drop menu on the top, EVERY. TIME. you open dgVoodoo, otherwise you're just gonna edit the "dgVoodoo.conf" that's in dgVoodoo's main folder and not Sacred's. So if you need to go back and forth a bit, maybe because you've made some mistakes or you want to mess around with the options for yourself, please REMEMBER to always check first if the folder you're editing in, is the correct one.

Now, there are a lot of options here and I suggest you inform yourself a little and experiment with what works best for your PC, but as much as this guide is concerned we're just gonna click on the drop menu under "Scaling mode" that's in the "Appearance" section, while we're still in the General tab, and select "Stretched, keep Aspect Ratio"

but ONLY if you intend playing in fullscreen (basically, because we have set up dgVoodoo, fullscreen will now stretch the image to widescreen, disregarding the aspect ratio, so we need to tell the program to keep it instead). If you otherwise want to play in windowed mode (be it on its default mode or by using this guide's fix) you can leave that unchanged (as in it doesn't change anything if you do it, so if you think you'll want to play in fullscreen in the future, you could want to select it).
Next, click on the DirectX tab and disable the "dgVoodoo Watermark" option in the "Miscellaneous" section, which simply added a watermark on the screen everytime you play.

The next option (still in the DirectX tab) is the one we set up dgVoodoo in the first place.
Under the "Videocard" section, there's the option "VRAM" where you want to put in the maximum amount of VRAM (which is basically the RAM, or volatile memory, of your graphics card) that you want to dedicate to the game.

You can check how much VRAM does your video card have, in Windows 10, by doing the same thing we did in order to check our monitor's refresh rate, so right click on your Desktop, click on "Display Settings", scroll all the way down and click on "Advanced Display Settings", but this time you also click on "Display adapter properties for Display #" (where # is the number of the display you're gonna play on, usually it's just 1 as not many people have multiple monitors).

The amount of VRAM is gonna be displayed in MBs to the right of "Dedicated Video Memory".
A word of caution, putting more VRAM than you have won't change a thing as you can't demand more than what your video card can output, but if it ends up messing with your screen with graphical glitches or crashes, do consider turning the VRAM down a few MBs in the dgVoodoo options, personally it never gave me any problems when maxed out but in case it happens you know what you need to do.

At this point, if you feel like you've finished setting up dgVoodoo, you can delete whatever folders, zip files and exes you have left, as you only really needed the .exe in order to access, and therefore configure, the .cfg file that's now in your Sacred's main folder.
If you think you'll still want to configure these options in the future you could store the dgVoodooCpl.exe file somewhere in your personal data or in Sacred's main folder (every other file we extracted and didn't use or the zip itself, is useless and can be safely deleted), just remember that you need to change the folder you're operating on, in the dgVoodoo options, every time you open dgVoodoo.

If you're having problems applying any of these fixes try checking the settings once again, they might have changed back to default after you opened the game (it might happen at least once the first time you do it).
If that happens re-do the fix, check again and if it stays you've done the trick.

If you've done multiple fixes from combining them from other sources and the game is giving you an unwanted result, try uninstalling it, deleting the game's main folder and re-installing the game.
If you don't want to do anything as drastic or you're worried your save files might be deleted (which you can always do a backup by saving the folder "save" in the game's main folder and paste it back once you've re-installed it), you could run a game file integrity check by right clicking on Sacred Gold, clicking on Properties, opening the Local Files tab and clicking on "Verify Integrity of Game Files".
It will basically check every file that SHOULD be there and see if they correspond, bit by bit, to its original counterpart. While this in theory should remove the possibility of any fix's incompatibility, it will not however remove files that SHOULDN'T be there (like the 4 .dll files and the .cfg configuration file from the dgVoodoo setup) so do not consider it a clean installation and if there are still any problems, do one as mentioned above.

If you can't set the fps counter in the Steam settings and it doesn't show up or if you can't seem to open the Steam Overlay it could be because you've opened the game from its .exe (because of the shortcut windowed mode fix or because you wanted to test the game out from its main folder) or it could be because you've enabled some compatibility options in the .exe windows properties (especially the "run it as windows X" compatibility tweak).

If you still can't play the game with a decent amount of fps consider checking your PC specs and confronting them with the game's recommended, and consider upgrading your graphics card, CPU or enhancing your RAM.
Although the problem is not so much your specifications but the fact that the drivers that would enable even a really old PC on XP to run this game at a smooth 60fps are no longer there in modern OSs and Steam is no longer available before Windows Vista, so your only chance is probably just upgrading your own PC.

For those who like to play around with all the different settings, especially with dgVoodoo and see if there might be other fixes or performance improvements that can be discovered, mind you a couple of things:

• I tried all possible combination of options but there's really no way to achieve a proper borderless windowed mode (so without the rest of your desktop visible) using only dgVoodoo. I know I can't stop you but don't even try it, it's a waste of time; the game is pretty rock hard coded in its resolution and nothing can change that beside going fullscreen.
  
• Changing the resolution in the DirectX tab doesn't change a thing, again the game is hard-coded that way and not even the 3d model will render at a higher res. There are no changes in the fps either and changing anything in the Resolution drop menu is a waste of time, don't do it.
  
• I've never tried it myself but from what I've heard disabling or even just messing with the AA filters in dgVoodoo is not a good idea and leads to all kinds of graphical artifacts. It's bad enough the in-game one so you should probably leave everything as it is and don't bother with it.
  
• Don't bother trying to give priority to dgVoodoo when it comes to deciding if the game has to be fullscreen or windowed, once again, the game is hard coded and doesn't take no for an answer. Use its Config.exe file instead.

And finally, if you have any suggestions, any more fixes, typos in this edit or need clarifications, leave a reply and I'll try to respond to everyone.