hi drlandy,
That looks like a good start, how many videos can you successfully play with what you have?
I would start by taking a look at the link that I put in my last post and using an external class to hold each of your movies. You'll want to modify that class to extend thread, here's some great info about using threads. Then you can do all the movie frame grabbing and drawing to your vertex-drawn frame to a PGraphics. Your draw loop on your main sketch will be simply responsible for grabbing and positioning each PGraphic on the stage.
im away from my computer right now or I'd post some code. I hope that makes sense.
good luck!
ak