So I decided to buy Gold today, downloaded it and now I see that there's the normal install file for GOG, but there's also 2 other types of files, BAC? or something like that. What are they, are they important and if so what do I do with them? Thanks for the info.

As well the game seems really choppy to me, almost like lag but I'm doing singleplayer and I've got the graphics down to the lowest setting and it's still kidna choppy...

Thanks

the other files are just part of the installer, large games are divided into a installer executable and what amount to additional zip files, for you lag question, what are the specs of your computer? even tho the game is older it can still tax systems, it likes lots of ram, and how far you have the view distance set too can have a big effect