Greetings:
First, I'd like to take a moment to thank the developers of Hyperion.NG. I can't believe how easy it was to transition to (from an install of Hyperion that is maybe 4 years old!) and how incredibly fast my LEDS respond using the same hardware I've been running for many years now.
I wanted to report that I was receiving a scrambled picture with my grabber. It caused the LEDs to respond with incorrect colors. I found that it really wasn't hyperion related, but after updating my old PI to a newer OS, all the screenshots were scrambled really bad -- as in the bottom was on the top, and the the middle was on the bottom... really weird.
I was able to fix this by changing my HDMI converter to PAL from NTSC and changing the config in Hyperion to PAL as well (I'm in the US, so I would normally expect to select NTSC). After that, everything is working great!
I wanted to share to maybe help someone else.