ColorDMDs are downloaded via a thumb drive from the website. They rely on the original eproms to work. It simply "colors" the code.

Interesting to see how this turns out.
You should still get the code version displayed before it goes blank if the MPU is not sending signals.

I pulled the MPU to DMD cable on my JP lost world to see what happens. Even without connection to the MPU, it still shows the name of the game before going blank.
If you're getting nothing, I'm guessing small cable or 5v power to the driver board.

Can you post some pics of your set up? The back of the colorDMD, the driver, power supply board. I want a visual look at everything.
BTW, I'm dealing with the same issue on a large DMD Frankenstein. Have mine narrowed down to the 14 pin cable or grounding issue.

Have you tried flipping just one end of the 14 pin cable, not both ends?
It wont hurt anything.

Bulletin 106 is only for jumbo DMD games. This is a regular size.

I would get a ground strap/wire to that J7 hole on the new driver board.
Another thought, is that ROM chip seated correctly, no feet bent under,? I've done this before.

It appears the holes have metal eyelets in them for grounding on the metal mounting screws. There wont be any traces, that's a giant ground loop around the outside of the board.

It means when the board is mounted on the metal bolts that hold the DMD in, the board is then grounded to the machine. The metal eyelets in the mounting holes touch the metal bolts creating a common ground.
You have it mounted on plastic pins, therefore the board itself really has no ground to the rest of the machine.

I'm also suspect of that slightly low 5v power.

With the DE games, he should still get the ROM version even if the MPU is problematic. I'd try changing that IDC 5v connector to a molex with trifuricon wipers in it. Might help with the voltage drop.
DE games can be very finicky when it comes to the 5v supply line.