I found a bug on ThumbVideo 2.1 which is released today. When app is started, only a black screen is shown and then nothing happens.
It seems happens only when “Allow Portrait List” switch is OFF in “Setting” app. It happens only on my iPhone4S, not iPod touch 4th / iPad 3rd or Simulator for now. Deleting and re-installing the app fixes the problem temporarily, but it will happen again.
If you encounter this, please turn that setting ON for temporal workaround.
I have submitted the fix version 2.1.1 to AppStore. Please wait a week or so. Thank you for your patience.