Enderman dances in a cupboard (3D animation & compositing)

A 3D animation & compositing project for uni, which I didn't pass. I understand why, but unfortunately my teachers refused to give me proper feedback and help figuring out why the shadow for example didn't drop as it should on the ShadowMatte. I'm not sure where the problem was.

I used Substance 3D Painter for the texture of the cupboard, and drew Enderman's skin in Procreate.