After a fresh installation, aren't you forced to restart the computer to finish installing the copy protection drivers?

If you exit the game, run the configuration program and hit the reset button, does that let you play again? Alternately, you could delete the configuration files config.div, slashed.cfg and slashed-d3d6.cfg in the Beyond Divinity folder (if they exist), to force the configuration program to recreate them the next time it or the game are started.

Try deleting the files in the dynamic folders;
'..\Beyond Divinity\Acts\Act1\Dynamic', '..\Beyond Divinity\Acts\Act2\Dynamic', etc.
These folders are used as a cache for the game. Files are created / copied there from the save game folder when you load, and written / copied to those folders when you save a game. The files will be re-created as required the next time you start Beyond Divinity. If there was a corrupt file in those folders, deleting the files should fix the problem.