LordRikerQ: Thanks for the links! Its great they put em up for free now, i think Gog should really just package them their installer, comyr and Pirates are probably the best modules IMO.
My understanding is that those modules come with DRM: the client checks with a master server to see whether you own the module or not. For some time, the server has just been authenticating all requests, but if it went offline everyone would lose access to the modules. Plus they only work while online as they need server access, although I've heard a few conflicting reports in that area.
The extra modules which are included in the GOG release were released without DRM on a disc as well as online.