Also, just a little note, for some reason, side B and Shielding causes the textures to become solid instead of clear, and gives them some odd properties...makes me dizzy...
I have been having something like this happen to me recently as well. And here's the weird part: it's not a character, but a specific costume. I can't seem to be able to do ANYTHING with Captain Falcon's Blood Falcon texture. I put a texture/model hack over it--nothing. I put said hack over one of Falcon's other textures--POOF it works! Go figure.
As to something that might help, did you make sure that you compressed the file right? If so, try using both the PAC and PCS.
Does the person he is over have to be able to crawl? I thought it didn't matter, and you could just add it in. By the way I am pretty sure this is being done over Olimar, but feel free to correct me if it isn't.