After googling this problem for about an hour I gave up and decided to ask the community. I've installed the BGR mod for NWN2 according to instructions, extracting the 6 archives to the my documents\Neverwinter Nights 2 root directory and merging the BGR folders with the existing NWN2 ones. However, whenever I try to start a new campaign through the New Campaign menu option in the main menu, it immediately gives me an error message saying "could not load the module, module might be corrupt or it was created using a newer version of the toolset and/or game resourse" (or somehting along those lines). I've never played NWN2 before and thus never installed mods for it before either so it might be a stupid mistake I'm making, but if anyone has any ideas they would be appreciated :)

P.S. I applied the GOG patch for the game, but it said the game was already updated. Don't know if that makes a difference? I've attached a screenshot of my documents\NWN2 root directory as well

You didn't state which version of the game you have. BGR requires both Mask of the Betrayer and Storm of Zehir, else you will get that error message.

Ah, my bad! Bought from GOG, Neverwinter Nights 2: Complete version, and all campaigns show up on the menu when you click on New Game ( original campaign, mask of the betrayer, storm of zehir and mysteries of the westgate, plus baldurs gate reloaded ).

The GoG version is fully updated and has all the expansions. You must have had a glitch in the download. Try to download it again.

That solved the problem, cheers! Uninstalled the game, redownloaded it and reinstalled it and it just worked this time around :)

solved.