Congrats on getting invited to interview! I'm glad it went well! First things first, get a handwritten thank you note out there immediately.
As for ding appeals - very few schools allow you to do that. Ross, for one, does. Most do not. Most don't even offer feedback on why you were dinged. That's why a lot of firms, including ours, offer Ding Review services.
But let's talk about that IF it comes to it - hopefully it won't! Let us know when you get in
I would have still appealed (or begged) even if the school doesn't have a proper appeals service. Shows perseverance and toughness...i thin they would have liked it.