This is not a bug, it is made this way. You have to open the Pz3 when you want to work with Tagosaku and you should leave everything together in this folder. When you save it as a Cr2 the headprop won't be applied and that's why it loads without the headtexture. The mapping is different: the P4 man uses a single map for head and body while Tagosaku is mapped to use two textures: one for the body and one for the head.

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