I guess I missed the last pix with it on the cuecard....wow that is small, yeah, maybe some kind of rodent.....
looks too long to be a cat..... perhaps a possum or raccoon.probably not a dog, no saggital crest, and it's too short (it looks like it goes as far as the nose bones go). therefore probably not a related species either. Though I suppose it could be something like one of those flatfaced dogs, I don't know enough about their skulls to say.
not likely to be a rodent, too big, and they generally have complete bony orbits. That skull only has part of the zygomatic arch, which is more characteristic of carnivores. I think part of it's missing though, probably with the part that had the teeth in it.
maybe a cat, haven't looked at enough cat skulls to say. about the right size though, for a small cat.
Skulls Unlimited has an extensive animal skull selection (under "veterinary"). you might browse that. At the bottom it's got links to all the nondomestic critters.