Whats the history and is there a full schematic?

Hi All, Just found this great forum.
As a builder, programmer, and designer I’m interested in the 312 estim product and other stuff.
What’s the history here… is this an identical clone with custom firmware or is it a complete reverse engineered product with original firmware. I note someone mentioned the original manufacturer ET deleting files elsewhere.
I see people having faults etc. So is anybody able to give me a quick rundown on the events so far or links ( I can see some links to firmware I think and PCB gerbers but no schematics. )