In Illustrator CC every time I click Merge Paint I need to go back to Live Paint > Gap Options > and reset Gap Detections to "Paint stop at Small Gaps". Despite I set "Paint stop at Small Gaps" as my default many times now, it seems that Illustrator CC does reset it automatically to "Custom Gaps" and therefore Merge Paint doesn't work correctly. A nightmare, I am forced to use Illustrator CS6!
Any tips?