[General Woundwort]

Aside from graphics mods like FQM and the Image Mod, most mods are not "stackable". Often times, two mods will alter the same data files (and sometimes the same items within those files), so simply combining them would yield a buggy unrunnable mess.

Now if you want to add races to your game, all you have to do is add their folders to the "race" folder. As long as the data files are compatible with the current Version/mod you're running, you're all set.