Well of course it doesn't use .pac and .pcs. I think those are brawl specific.
You need to be looking for either .brres files or something different that contains the models.
There are no .brres files I could find.
And .pac is NOT brawl specific or even Wii specific.
Blazblue Continuum Shift for PC, XB360, and possibly PS3 use .Pac files.