When I attempt to choose a custom skin, it is always invisible. Even uninstalling and reinstalling the app doesn't work. I went into the game's files and located the skin "custom.png" that was set for the game when you go back to see the previous custom skin you've chosen. I tried to see if it would fix the issue by deleting it, but that didn't work either... This glitch is very severe in my opinion. It carries over even if you don't have the app installed.