I think this little peculiarity only occurs when you edit the actual text of the .obj/cr2 to remove the materials. Doing so in a modeler of any type will invariably define a "default" material. This is why when editing text objs and cr2s, one must be careful to leave the preview material intact within the cr2 or... poof!

Also, in order to eliminate unwanted materials within a figure via text one must delete them from both the obj and the cr2. Doing so to only one of the files causes poser to reestablish the deleted materials via whichever file was left with the intact definition. Just be careful to leave the preview material alone in the cr2 when using this method.

Nice tutorial vilters, especially your method of creating a single map.