I 've tried multiple times with BG2 but cfg fails to load the specified folders no matter if I use GOG Complete version (not Enchanced) and just point it to PROGDIR:BG2 (since it has different file stucture over iso rip) or PROGDIR:BG2/CD2 or PROGDIR:BG2/CD2/Data/ or full path such as CD1=Work:Games/Baldrus Gate Series/bg2 etc (for usual iso extracted data downloaded from archive.org).

Can anyone confirm if it works or not on his system?

BTW, checking with IW2 is a bad example since game is not completeble under GemRB (even latest versions).

TBH, I think that the port should support GOG versions straight out of the box which have the exapnsions pre-installed.