Game froze browser and then laptop w/ two moves left, about to 3 star complete level 480 Farm Heroes

I was playing Farm Heroes (and doing nothing else on my laptop, no other browser windows open) level 480, about to complete it with 3 stars and 2 moves left, when the game/browser/laptop froze with no warning.  No script or debug offered, just froze.  Just last week I finally (!) figured out how to access my reward resources, and stupidly used almost all 479 levels earned ones, and then regenerating ones up to complete this hard level when it happened.  Is there any way to get some, if not all, of them back?  So frustrating plus I have no idea how to help you to fix this for future or even reproduce it (since I can no longer use up all my resources).  Sigh.  Help?