BKGaming: There is a way to do that I believe by changing one of the Galaxy files. Assuming both versions have a different EXE. If you are interested I can try to see how to do it again.
Mawthra: If you have a link or something, let me know... and yah, there are two EXE's... both the classic version and enhanced versions are in the directory... game folder doubled in size, it seems... fuill install is like 54GB
I think you can do this by looking at mike_cesara guide to for adding external games to Galaxy. It's not exactly the same but he kind of shows how to do it. Basically you have to modify the goggame-#.info file. This part here I believe is the relevant part:
"name" : "multi", //new menu entry
"type" : "FileTask",
"path" : "ioWolfMP.x86_64.exe", //and path to another executable
"workingDir" : "",
"arguments" : "" //optional command line arguments (ie. +set sv_cheats..)
Which should create an additional menu entry to the original one. Change the name to Classic D2 or whatever you want and set the path to the classic exe. However, if this file is updated when the game updates you will have to re-add it until GOG does it officially.
So basically add:
{
"name": "Classic D2",
"path": "Path_to _game.exe",
"type": "FileTask"
},
https://www.gog.com/forum/general/adding_external_games_to_galaxy PS: I would also suggest using a code editor so it's properly formatted and so you don't mess up. Make a copy of the file first.