I would suggest you download Cute Mob Models 2 instead: https://www.curseforge.com/minecraft/mc-mods/yarr-cute-mob-models-remake
Discord: https://discord.com/invite/3qmMVa97eM
Twitter: https://x.com/CuteMobTeam
This mod replaces the vanilla mobs with designs used in MobTalker by AT2. A continuation project of the popular japanese mod.
The earlier versions requires Risugami's ModLoader, which can be difficult to set up. I recommend you watch some tutorials on how to get it to work.
Rename .jar to .zip for the mods to work properly.
The Cute Mob Models continuation mod was originally created by Yarrmateys, and is now Open Sourced.
Screenshot of Yarrmatey's post:

If you found something that doesn't look right, is probably a bug, or is just flat out broken please head over to our Discord to report it!