Well I think I got it, I added bones for the corners of Izumi's mouth, this should help in, certain, animations, and of course allows me to make or improve some shape keys in blender if I need to. Izumi's mouth looks a bit different when her mouth bone is being used but I think it looks a bit more natural this time since you can clearly see where the corners of her mouth are at all times, also the FK bone for her mouth is no longer visible, only the IK control bone.
Izumi 2.1.3 is already public but just a heads up, Mediafire seems to have switched to Https for their urls, so if you have links for my stuff and it gives you a 404 error, try adding an "s" after Http, that should work.
The Blend file has been updated too and it is already up in the folders.
There was a missing texture in the "alt textures" pack for the bunny girl outfit, I corrected that and re-uploaded the archive.