NO it's not bannable,
i guessing their has been a rise in ban's,
this is probly because hackers are tricking people that these are customs skins when actually their hacks, = ban,
thats what this means;
Use caution when installing any game modifications, such as scripts or custom skins. Only download custom content from trusted sources. Hackers sometimes maliciously disguise their cheats to cause others to get banned.