I have a Famicom (HVC-001) that has the NESRGB kit installed and the Voultar NESRGB-IGR switching circuit.
The system works fine with the original Everdrive N8, but with the Everdrive N8Pro it will not boot. After spending a bunch of time with it, I was able to figure out that if I turn the power on while holding down the RESET key the cart will boot and work - BUT the system constantly palette swaps (which is normally done by holding Right one the D-Pad and press Start and Select at the same time).
If you turn the machine off and back on without holding RESET the cart will not boot.
I spoke to Voutar and got the following response:"Sorry my man, I haven't the faintest idea with the Everdrive N8 Pro would cause that sort of behavior.
I know that the reset timings were dialed in to accommodate the original Power-Pak and the Everdrive N8, but I haven't any idea about the Everdrive N8 Pro.
-V"
Here you can see the system and the palette swap happening - the LED on the front of the Famicom is an RGB LED and each color indicates a palette.
http://www.c0op3r.com/images/Amiga/Famicom%20HVC-002.MP4