uv_1 does not transfer to my mesh and deforms in the CAS whe

I'm creating my first mesh to make some shoes for the game, with a mesh I downloaded from the internet. Everything was going well until I try to transfer the uv_1 from the base mesh of the game, because it gives error and it doesn't transfer with the data transfer in blender 2.78, but the original uv of my mesh remains in uv_1 and only the uv_1 of the visible leg is transferred.



In the CAS when I want to change the size of the shoes it deforms and I don't know how to fix this error.



Please could someone help me :(

my mesh: www.mediafire.com/file/n1qed487rm8ohs0/mallajuego.blend/file