The K2 print preview has no scroll-bars. So you cannot see the entire document that you are trying to print. This needs to be fixed. Printing works as expected.
Thank you for reporting, I created an issue into ja bug tracking system here http://pm.joomlart.com/browse/JATCWALLJ25-241 for developer to have further checking and fix this issue then, you can also follow the issue to know when it get fix
This is solved in the stable release.
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