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Can anyone advise if they can get Thief 3 to run on a User-level account on XP?

My physical copy of the game will run from an Admin-level account, but not a User-level one. XP does not have a function where I can automatically tell XP to run a program as if I were an Admin, and nor would I normally want to give an game that access.

Upgrading to Win7 is not an option now or in the foreseeable future.

If GOG's version will run with User-level access I will be very happy, but I won't buy it otherwise.

Thank you.
Some good questions...

I have the Steam version, and it works fine (once I apply a fan patch)... But it GOG's version is more stable, has all the necessary patches, resolution patches, etc. I might think about getting it... Especially for the no DRM....