Just a quick note for your information - the problem is already addressed and will be corrected with the next update: When showing menus on top (e.g. for sharing) StitchBuddy HD 3.3.0 often redraws the underlaying design, causing some flickering. This might remain unnoticed for small designs, but is quite annoying with large files, whose are taking more time to redraw.
As mentioned this issue will be fixed in some days 🙂