Just throwing this out there…
I’ve pushed up a very early release of my firmware image for Glowforge units with a factory control board.
The image boots to a basic Linux install, with support for wireless. It doesn’t do anything else, yet. Running it requires you to install the microSD slot and have access to the serial port.
Would be nice if some people would be interested in collaborating, as it gets old just working on this stuff by myself. 
I’m can imagine. I wish you had more help. Your exploratory evisceration has been very helpful to me and others.
I only became aware of this project very recently, after convincing my school to buy a Glowforge and then discovering, much to my horror, their “business model.” I know I screwed up - I should have researched it more carefully - but I had no idea that anyone would do something so awful. So now I am very hopeful about your project. And I’m very eager to help! I am a complete noob when it comes to reverse engineering control boards and writing firmware, but I should be useful somehow. I even teach a circuits course to engineering students! Please let me know how I can help.
tate
I look forward to your involvement!
Tomorrow, I’ll be posting simplified instructions for getting console access if your unit didn’t come with it. This method requires significantly less soldering skill.
I’ll also be posting up instructions in the coming days on building and installing the firmware images.
Quick update…
Latest commit has full control of all of the hardware on machine.
I’m writing a quick kernel driver for the head to save the need to do raw i2c read/writes from application code, and give it a sysfs interface like the rest of the hardware.
After that, I plan to work up a Python library for interfacing with the hardware at a higher level before whipping up a simple Python based control program that will connect to the GFUI.