Very Nice! I like the music too. GG has a demo area on the server and I am going to put it there for future use.

P.S. GG is still working on Shake, Rattle, and Roll (Elvis) -- which is really Ripple, Roll, and Slip + Edges. It has been very time-consuming and meanwhile he found a critical section deadlock that is in the way of completion. gg/Phyllis

I have done a short Demo video (6m14s) with the description to show the use of that powerful feature.
In the demo you can see that I use four video source, but you can use more. I hope it can be useful.
File: Demo_MultiCameras-ExpertUsage_OpenMixers.(mov)
https://streamable.com/c40ia