Well designed, saving progress problem – Nonogram Plus Review

The game it's well designed, and I actually enjoy playing it, I try I few others, but I think this nailed with the design and the way to play it... But it have a BIG MAYOR ANNOYING problem with saving the game progress, sometimes it save it, some others it don't... And it's frustrating when it happens, that's more often that what I can handle it... Every time I finish a picture, I go back to the main screen, close the app and immediately reopened to check out if the progress was saved, most of the time, this way works... Please, fix this bug SOON!!! And I will update my review Uptade: the bug remains despite the recent update!
Review by JDFabbiani on Nonogram Plus.