I have added new note to my LEGO® Minifig Creator 3D App Store page requesting users visit this site first before leaving negative review comments. Here you will find known issues and fixes, details on the next version of LMC 3D, and you can also contact me for additional assistance if required!
P.S Please make sure you are running the latest version of iOS on your device, Apple's new releases not only contain the latest and greatest new features, they also include lots of improvements and enhancements which make your device increasingly more stable.