I'll think about equines. I won't guarantee that I can create such a face morph with the current mesh, but I'll think about it. I'm fairly certain I could manage the hooves and tail. I wouldn't mind giving it a try, if only to create fan art for Flinthoof.

Speaking of anthro equines ....

Lemurtek has a pair of zebra-folk among his freebies over at 3-D Arena. They're based on the P4 Male and Posette meshes, and have hooves, tails, and digitigrade legs. The heads are mostly human, unfortunately, but maybe you could replace those with the P4 horse's head. The Poser 4 manual describes the process, using a bull's head to create a minotaur as an example.

You might also want to pay a visit to Vista Internet Products. Debra Ross has an anthro unicorn mare, Rhianna, in her store.