[Kugelfang]

Yeah, I suspect it's a Pep issue, too. My guess would be that since there is no color rgb data for the transparent parts of the *.png file, Pep is assuming an rgb of 0,0,0. Which IS the rgb value of black. (Or the rgb value actually is 0,0,0 but that most applications would also read the alpha channel which tells the application that the area is actually transparent and to ignore the rgb.) I've come across other applications that mishandle *.png files like that. It's kind of an 'old school' issue but I don't know how current Pep actually is.

Just out of idle curiosity, if you assign a material color of red to a part of the *.obj that does not have a texture applied in Blender, does Pep show it as red? I'm wondering if you're actually seeing the material color in Pep, or if white is the default for an untextured model.

--jeff