No .map files for demo? No null texture?

Hello all,

I'm going through the map2dif tutorial and trying to get my head around it.. I'm checking out the directory structure and comparing it to how the process is explained in the tutorial (where textures are stored, how the .dif file is stored in the same folder as the .map file, etc..)

However, I'm trying to find the .map files, and they're not there. Are they stored elsewhere, or were they removed from the distribution/demo?

Also, in a tutorial, I read that you should apply a null texture to a brush that is to act as a portal so that it won't be rendered in-engine.. However, I see no null texture in the folder for the "greathall.dif", nor its parent directory. Is no null texture used for the portals in that interior, or are there no portals at all?

Thanks..
Mike