Wow, this is really excellent! At first I got a bit confused because I thought that at the house-guessing phase, I could move around, but reading some comments here made it clear that I just needed to place houses if they exist in the snapshot. This is a really fun memory game that definitely tested my ability to memorize the house locations!
I do think a tutorial explaining the process would be helpful. Though full disclosure, I am on Mac and you mentioned this doesn't run great in web on Mac; I could still play it after waiting for it to load, and still had a really fun time, but the initial instructions may have been obscured for me, so that might be why I got confused at first.
Either way, this is an excellent entry, well done!