The games offered at GOG.com are the same versions as those published back in the days. We don't have the source code for the games and we can't do any in-game changes. Although our programming team is making some magic to make every game work on the modern OS. For example we have prepared custom installers for every game which helps to bypass some of the incompatibilities. Generally we're doing whatever we have to do to make it as easy as it can be to download a game, install it and play without any problems.