Video not uploading for anything over 8M and some contest entries erase without reason.

I thought it best to do a screencast about this issue:

P1: https://www.screenca[...]/t/QcUeg947wtP8
P2: this is not uploading for me currently - but as you can see from attached image, when I go back to view the video in the contest it says "no longer exist". The 1st video you saw me upload in the screencast works fine... its a second video that gets erase with no reason...