I'm quite happy to upload a video of my attempt to get downloaded google play apps to work...I can prove these apps simply do not start. (private message me with an email address?)
Again, the 3 apps I simply cannot get to start on reboot (there may be more, but I'm only concerned about these 3) are:
Timely Alarm Clock
SB Wallpaper changer
All are readily available from Google play. All of these are 'locked' in the White List, and NONE of these auto start on reboot.....Strangely, even though Timely Alarm Clock does start not on reboot, when you actually 'open' the app, the alarm suddenly goes off (for an alarm set minutes ago).