it works for me using the latest stable and the preview builds on win 10 pro 64bit

This is how i did it:

1. Extracted stable build into it's own directory away from galaxy or steam.
2. Copied over base directory from installed GOG version to RBDoom-3-BFG-win32
3. Extracted d3bfg_mod_launcher_v1.2 into it's own folder then copied and pasted the folder and files selected in attached picture to RBDoom-3-BFG-win32 root directory.
4. Run the modlaumcher exe
5. Install mod permantly by copying base folder from one of these:

Doom 3 BFG 2.0 MEGA MOD
or
Trent Reznor's sound pack and Phrozo 1.3 effects mod

And for just wulfen and monoxead texture pack with no sound change use
Wulfen & Monoxead HR texture pack (full)

www.kot-in-action.com/forum/viewtopic?f=28&t4436&sid=1f4c3dd36317fc83104d142b73bded43

to RBDoom-3-BFG-win32

So the GOG version of Doom 3 is literally the worst version available.

Does anyone know whether it is possible to only play the expansions in the BFG Edition, without finishing the main game first? I'd like to play the campaign in Doom 3 Vanilla and only switch to BFG for the expansions, if that's possible.

The expansions are freely avaiable to play, you don't have to play the main Doom 3 campaign to play The Lost Mission or Resurrection of Evil.

Cool, thanks for the quick reply!

Sorry it's not working.
Maybe try this page:
http://steamcommunity.com/app/208200/discussions/0/846958724796395601/

and

http://steamcommunity.com/app/208200/discussions/0/487876568235225068/

I think i read somewhere that changing RBDoom3BFG.exe to Doom3BFG.exe worked for one person.
Only other things I can think of are running exe as admin and trying compatibility modes like win 7 or xp3 and making sure virus software isn't blocking anything.

I'm playing Doom 3 for the first time right now and I'm glad I got the BFG version.
1. Because it include doom 1 and 2 (so I don't have to buy them). I love complete package.
2. Because it's already too dark and the flashlight is already limited... Also there are already too little ammo. Doom 3 is already slow, I think it's better if you can get more ammo and shoot things.

PS. I don't care about mods and multiplayer.

Still hoping GOG adds the original version :(

Hoping for the original version also!

BFG Edition is censored in all versions, in all locales. Also, the older doom games coming from inside it, are censored, too.

Vanilla version was uncensored and also had some gameplay differences; graphics ones aside.

That's the reason i won't buy it and will wait for the original bundle, to come here. But with recent changes in GOG's business model, policies and code of conduct (both towards partners/associates and fans/customers), probably that will never be. GOG of today silently pushes censor in.

How was it censored?

Those who stalk and screenshot my posts to downvote en masse, made my rep drop from ~ +500 to -282. Lower than +10 reputation, you are no longer able to post links; so, i apologize, but i am completely unable to link for you, articles, gameplay videos etc, explaining things. BFG Edition had a number of changes qualifying as censorship; same goes for the older doom games that are bundled inside it.

Just search it out, it's easy. Also, sad as is, GOG seems to have silently abolished the "offer uncensored games whenever possible", tenet of theirs. Only me, knows of 8 games that are censored (5 are mentioned in GOG-Wiki and in forums "list" thread) and it is public knowledge, that GOG turns uncensored games down now, at this point in time ("Too niche", anyone?). I wouldn't expect the classic bundle to arrive here, as is.