This started happening about a week ago....for some reason whenever I try to use actual SWBF2 (not BF2_modtools.exe, that still works fine), as soon as I get to the instant action screen there's a lot of lag (???). As soon as I manage to select a map and click launch, cut to black screen with cursor, freezes, doesn't respond even when left for half an hour.

Anyone had something similar/know what this is caused by? Obviously I can't post an error log because BF2_modtools works perfectly well.

Is the problem localized to SWBF2? What have you done in the recent weeks to your computer? When did it first start showing symptoms? Has it been a slow onset/immediate change? Etc.

Immediate. Things done recently - installed newest XSI mod tool, run several full virus scans, edited fire wall to try and let BF2 to connect to Gamespy servers, installed Bfx 2.

Ah...just remembered the BFX one. After installing it was the first time BF2 started messing up. So I uninstalled it, removed all BFX files...still messing up. :S

Tried uninstalling and reinstalling the game?