The DDS extracted from PS2 models aren't DXT3, they are 256-color paletted-DDS. Get the program I mentioned
here, then you shouldn't have any problems.

For offsets, you have to follow noelemahc's tutorial; you can't do it the "usual" way...lol
EDIT: If you can see the skins in XML2, then the PS2 models should work in MUA, too!!