New Zealand was missing for me. I didn't think much of the huge hole where the country should be. Guess I'm used to seeing it that way. (Also sorry to all the New Zealanders).
I think this quiz is broken now. My 'guessed' box is out of 145 and no countries appear to be missing (and it's accepting every single country I type). So confused.
After time ran out, I still hard trouble finding the tiny red dot that is Burundi.
I even zoomed like in the Pacific islands like Fiji and still didn't notice.
Sorry to all the New Zealanders
edit: just got them all, but Armenia and Azerbaijan held out together for a long time after again getting stuck on 18!