The firmware is not mine, but if it was running before you should be okay. The LCD says mendel ready, mine says something else. Don’t worry about it for now I hope to release a new one after I update the build instructions.
So home is where it is, or where you power it up. Hard to explain really, until you figure it out.
When you power it up the screen reads 0,0,0 that is home. If you move it with your hands it is still home, screen still says 0,0,0. if you use the lcd or software to move it, it is not home anymore and will return to it’s last 0,0,0. Hope that makes sense.
This is not set up like a 3d printer in that regard. This does not home before every job (it can but best not to).
To start a job move the head to exactly where you want it to be x,y,z by hand. Turn it on. Start your GCode. Thats it! It starts from exactly where it is.
I hope that makes sense, if not I’ll have more coffee and try again.