Terrible bug in iOS 7

I love Nanostudio and ive been using this app for 2 years. But with this last update something went terrible wrong. Twice in a week ive lost the work of hours because the app didnt save the progress, despite (obviously) repeatedly pushing the save button while working on the track... Everyone who writes music knows how frustrating it is to lose the ideas and the work of an entire evening. Please fix this, i cant trust this app anymore...

Sor82 about NanoStudio, v1.43