Thank you 14+! I've actually let the two of them have a little face time, since Gizmo had stopped growling and hissing. And he actually groomed her today, I was so shocked since I didn't think he'd warm up to her nearly so quickly. I was just letting them run around the bedroom and they were freaking me out. She is growling and hissing, so I'm thinking she hasn't warmed up to him just yet, and he seemed to be getting irritated with her, and getting rougher and rougher in his play.
Then she started letting me know she's hungry (she's incredibly vocal, holy dog!) so she's back in her room for a snack and hopefully a nap. And he's laying outside her door. But I'm glad to hear that things are going normally, and so far I don't seem to be screwing up too badly. they're going to have to learn to play with each other, I think, since Gizmo was hand-raised and hasn't been around another cat since he was about 8 weeks old. I admit to some nail-biting, thinking about that process.
and btw, any recent pics of Dart? I miss him!