Oh, I see now. You have to HAVE printers, that are defined in the code. For example if you have only Autolathe and Hydraulics bender, you have to comment out all other printers from the code, otherwise stack will fill with blank entries and cause errors in the program.

add the lines after push 0 at line 21 then it worked for me

me too... 🙄

No matter what i try, it shows error on line 42- device not found.