The freezing and resetting only happened today; it certainly wasn't doing this yesterday. Not sure what's changed as there doesn't seem to have been a game update, but I hope the devs can fix it soon!
If they ever announce a global pandemic IRL, we should all move to Madagascar. If we're clean then we know we're safe there, and if we're carrying the disease then it's our one chance to get the bastards! :p
If you created two more achievements and gave one star for each achievement, you'd be able to earn enough stars to purchase all upgrades. Would love to see this implemented for the completionists. 4/5.
The one thing I would ask for is a "slow" function so that if you're stuck you can slow down the shapes a bit. It would be a huge help for some of the later levels.
Sorry about that -- I just notified the developer about this problem.