Thanks Andrés. I now understand what you mean by flow separation on the bottom of the airfoil. This is due to too large of an elevon deflection. Large control surfaces ( chord and spanwise length) will combat that sort of separation (and tumble).
You can bet, the CG is moving forward. I have stuffed as much lead as will fit in the tiny space available in front of the servos. If I need more, I'll replace the LE strip with lead at the nose. My next test flights will be at the beach, which will allow much more air time. During 1st Flying Day, there were also other flights that had a more aft CG than the ones shown in the video.
The original CG was from the original Nurflügel (Ranis program) output that I got from IG Horten member contribution. That file is attached.
If I understand you correctly, having the split elevon act as one would be the best approach for both elevator AND aileron, no drag rudder required. I will try it, along with any other combination I can dream up, including the drag rudder. I'll attempt to fully test each approach with a dedicated video for each. I've yet to try the crow function with the split elevons.
I've always noticed that flying in ridge lift, such as at the beach, makes any plane perform better. Not just apparent glide ratio, but less bad habits, like tip stalls. The true test is slow thermalling flight without ridge lift. If it doesn't tip stall, spin and tumble, I'm happy.
This should be an interesting test bed for me.
Maybe for next test flight I should provide a live video link to your cell phone.