Hi guys - I'm really sorry for the length of time it's taking to respond - we've been quite amazed by all the feedback! Thanks for the help and support!
The thumbnail crop will return!
Due to the terrible performance of the old servers, we decided to speed up the launch date to ensure Blipfoto didn't grind to a halt! Unfortunately this means that a few of the existing - and new features - aren't quite ready yet. This should be at the top of the development chain! (The next couple of days will be spent bug fixing and technically fixing any major issues picked up by the community!) Thanks for your understanding during this transition time...
The existing chosen crops should return when this feature returns too!
I hope this helps!