ptex
3D Coat/Blender notes: Getting ptex textures from 3d Coat to Blender
tl;dr: bake the damn things.
After painting, from the paint room go to Textures > Texture Baking Tool
Fill in the stuff on the dialogue box as appropriate (I have no idea how correct my settings are, I tend to take a best guess with anything I don’t know :P)
Export the model as a .dae
, import into Blender. It seems to import as many Ptex materials as layers you used in the 3d Coat’s paint room. I used two layers for the vaporeon model (one for colour, one for displacement). Set the materials up to use nodes and add their files (which will be named to go with each layer, e.g. anything with PtexPlane0 in the name in my case corresponds to PtexMtl0 in the material list).