Custom Skin Packs: Slim arms Revert to Default Alex

Maybe this is a bug honestly I'm not sure but, usually to save photo space on my phone I just import skin packs with skins I use 128x128 skins I use or make so that I can change them faster, and don't need to keep it saved In my photos. But lately when I try to use a skin with slim arm it doesn't work and reverts to an Alex skin. I've tried everything from manual importing it from files to using a different application. Other that when I use just the normal Import via photos the skin works perfectly fine.