At first, sorry for my English (I'm Spanish and this is not my strong point).

Problems with the game at Windows 7 64 bits:

1. I can't play it at fullscreen, only in window.
2. When I play in Window, I see 2 cursors of the mouse: the cursor of the game and the cursor of windows.
3. I can't use many of the actions, like the stealth.
4. Excesive FPS and I can't limitate them with the NVidia tools. It's the first time that I can't do this.

I installed the unnoficial patch and nothing, the problems persist.

Thanks and sorry for my English again.

Try Arx Libertatis, it might work for you as provides 64-bit compliant exe. While the 32-bit version had couple problems when I tried it (XP Pro 32-bit), few people that used the 64-bit version said it worked perfectly for them. If you experience same problem as I did, you may want to reinstall the game without the UO patch to see it makes any difference.

Oh and if you hanvent already, install the game outside program files to avoid permission related issues (you should do this with all games anyway). C:\games or anything else will do as long as it's not inside program files folder.

As for stealth, controlls are difficult in this game and need lot of time getting used to. I still failed to steal occasionally with no apparent reason (it just didn't work) after playing game half way thru.

I hope they release new build in near future as they've made lot of commits in past three months.

I'm running Windows 7 64 bit Professional and have none of these issues.

What is your video card, sound card, mobo, cpu, how many gigs of ram, etc. You need to be more specific.

I'm running Arx Fatalis [Retail box version; patched-up to V 1.21 English] w/ Arx Libertatis [x64] here on my Windows 7 64-bit PC.
No problems here. :D

Like I said I'm using Windows 7 professional 64 bit.

Try limiting the game to 1-2 cores via Task Manager Processes (right click on ARX.exe or something similar, then click Set Affinity. Set the cores to only 1 or 1 & 2.

Sure would be nice if gog coucl bother to support it on Win 7 - especially if it's close enough that it's working fine for some people.