Hiho,
first, download the updater here -->
http://www.festbierbude.de/component/
option,com_remository/Itemid,26/func,fileinfo/
id,15/lang,de/
unzip it and copie the folder in a random directory, f.e. C:\ or c:\programs
double-click "Downloader.GUI.exe, "Benutzername" enter your FBB Homepage Name and your Homepage PW
Next step "Pfade" "Pfad zu Power&Glory" means, the folder where you installed your GTR2 and the Power?Glory Mod.
Next "Pfad zum FBB Archive" create a new folder at any place/directory you like and set it here. click ok.
Note: the updater needs the net.framework 4.5, you can download it here -->
https://www.microsoft.com/en-US/download/
details.aspx?id=30653
Besser kann ich es auch nicht...
Glück auf!