Hello, I have a question to gog.com staff:

I have been wondering if it would be possible from you to allow us to download ONLY doom.wad or doom2.wad, since those are the only files, required while running various source ports. Players who would like to play such ports do not need any other files, especially behind installer - doom2.wad is all we really need and it would be really nice if we had direct access to it.

Can it be done?

I wouldn't expect this to happen, to be honest. Probably at the instruction of Bethesda, as I can't imagine they would want the data files distributed without the official game files.

In any case, the installers for the Doom games are small, and you can use a program called InnoUnp to unpack the installer where you can get at the .WAD files without installing the game. Them if you wish you can delete the installer.