Pretty much what scott says, most V3 textures still come as a MAT pose and will unzip to your pose folder, Select your V3 figure, find the MAT pose and double click on it to apply to all of the V3 skin.

P6 doesn't "officially" support MAT files [acording to the manual] but they do work and I think most people still use them although some do use the new way [material room].

Injustice will be avenged.
Cofiwch Dryweryn.