Newt, I appreciate the response, but it's not a capx issue - when I open a new project and load the video it still comes in upside down. It's an app issue.
its probably a browser cache issue, or windows compatibility cache issue/localstorage cache thing.
However
you said it was around 1 hr difference between the presentation and your test so there is no way you changed your Windows or C2 version between that time also..... so it only remains the fact that it might be your graphic drivers from your laptop, that have quit'd on you, or even worst the graphic card itself its to old and wants to park in the GPU Heavens. Which sounds more probabilisticly possible from the mentions you did.
P.S that big title based on your frustration today shouldn't be like that ... we all feel the frustration when stuff goes wrong when we expect them the less.. however is not the reason to ask for help in a harsh manner, its a high chance you will get a harsh response or probably 0 solutions.