Thanks for the report. I initially suspected that it was because some people had older OS versions, but that does not seem to be the case anymore.
One person whom I was in contact with throughout the day was able to solve the issue by re-installing ProShot. Earlier in the day after a re-install, the issue still popped up. He then tried a re-install a few hours later and it worked!
I can't replicate this error on any of my devices (Lumia 920, Lumia 810, HTC 8X), nor have I ever had this issue while developing, so I'm pretty stumped how to debug it. For those of you who are experiencing issues, can you please uninstall ProShot, reboot your phone, then re-install? After an entire day of bug-hunting, I can not find what could be causing the problem. Hopefully tomorrow I can get in contact with someone at Microsoft for help.
On the plus side, I've been able to slightly increase performance while reducing power consumption though some neat little tricks.