The Brushes are not on the zip files.

I think I've heard people ask this before, but I don't know the answer. Let me pass it on to Adrian, he's the wizard that knows everything around here.

Hi Toby kklaus ,

Did you place all the .zip files in one folder and then extracted (only!) the .zip001 ?

This is a so-called split archive and if you unzip the first, all the others get automatically extracted (at least with 7Zip, but there are others, that also recognize and extract split archives).

Maybe Kent knows. Lets turn on the bat-signal @theluthier

Apologies for the confusion. Keep in mind "brushes" are not included but rather the alpha/stamp textures to use with Blender's standard sculpting brushes are what's included in the source files.

This is what the source files directory should look like:

Is that how yours looks kklaus?

kklaus that should mean that the .zip.XXX files weren't unzipped properly. Check this thread. Alternatively you can check these instructions on the blender market page.