Mine was giving the Runtime error when I was trying to produce the movies, either sending them to Youtube or converting them to a different format. I installed the latest graphics drivers and the new DirectX drivers, and that problem went away.
Now, I have a new problem!! PD8 is crashing, without an error message, when I'm looking through the menus to import new media files for the current project. It does this pretty frequently now.
Explorer also started crashing a lot while PD8 was running. Not sure if that is related, but it could be.