[propbeanie]

You are most likely running into the Windows OS thwarting your mod activation Paul_Panzer15. If you use the default Steam install, the SH3 game ends up in "C:\Program Files (x86) \Steam \SteamApps \Common \Silent Hunter 3..." or similar. Anything with "Program Files" in Windows is a 'protected' file, and Windows will rollback any changes made to exe, ini, cfg and other files of a 'system' nature. If you have a 2nd viable hard drive to use for installations, then you could un-install SH3, and then re-install it, but put it in a new Steam Library on the 2nd hard drive. You might have to re-install Steam and SH3 both, if you do not. If you have other games, it can get a bit time consuming. But the path to SH3 is probably what is making your game not function after you install GWX into the SH3 folder. You should also delete all the files in the Save folder, which defaults to "C:\Users \UserName \Documents \SH3", and clear all of the old data in there. SH3 will rebuild the info with new data when you run the game again.