Redbook audio aside, the Mega/Sega CD version of Wolfchild is essentially identical to the Genesis version, save for on minor quirk...
In the Sega CD version, "Stage 2: Dense Jungle" has a missing background layer (layers?). When comparing with the Genesis version, you can tell this didn't seem intentional at all, and it might have happen either due to a rushed port job or... plain old forgetfulness?
Assuming both Genesis and Sega CD versions of the game share the same code, how hard would it be to create a patch the ports the missing background layer (layers?) found in the Genesis version back into the Sega CD version?