It's just part of the process. The ice will crack especially at really low temperatures. I just let the cracks fill back in on the next resurface, if it doesn't fill right away I may let the homeboni sit for an extra second or two to fill it up.
The worst is when you find the crack while skating with the blade that seems to fit perfectly into the gap. Or if you hit it just right and send a chunk flying, then I'll resort to the slush/puck method as Skate-Hard suggested.
To answer your questions:
1 - No
2 - No
3 - No
Making Backyard Rinks from 1999-2015
Twitter: @kevmac_5 or @macisaac_odr
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