will have to answer this one, or he should help somebody write a FAQ.
Basically there are like 4 degraded levels that your account fall into over time, each one lasting a number of weeks.
It's something like:
1st level down: you can't upload more pictures, but everything else works
2nd level down: visitors to your gallery can only see medium-sized versions of your pictures (but you can still see and back-up everything)
3rd level down: visitors can only see thumbnails, but you can still back-up.
4th level down .....
I forget exactly how it works. But the basic goals are:
-- trust that your lack of payment was an accident and not screw over your viewers
-- give you LOTS of time to download all your pictures to your local computer and get them off our servers if you don't want to keep paying (and there's an automatic tool for that)
-- not loudly notify your viewers that you didn't pay