AWESOME EDITING APP BUT......

Dont get me wrong this app is amazing but, recently Ive been trying to edit my video for my YouTube channel but when I go take a break from editing, I exit the app, then later I open it again then all the sound fx Ive put is put seconds before I had it before, thats not the only problem but when I come back some of my clips that Ive cut like overlays each other. SO PLEASE FIX THIS.

KiidReggiie_ about iMovie, v2.2.3