This is a super old post but if you need to rotate your character’s mesh -90 degrees, it’s because when you imported it you didn’t select the “Convert Scene” and “Force X Axis” options, select those when reimporting the mesh so you don’t need to rotate it by hand or do odd math for characters. Other than that and IK quadrupeds are treated the same as bipeds. I would also recommend only using the Collision Capsule for collision, don’t bother trying to use the Mesh.