For example, the extruder start g-code above ends up as ��� (or however your text editor shows unreadable characters). It isn't constant. The same start g-code will work perfectly for another file, or it'll only be garbled for the first 10,000 lines of the g-code file, etc. and appear normally after that.
I'm trying to implement a section of G-code during a tool change, shown below: EXTRUDER START G-CODE ; Start Extruder 1 M211 S0 ; Turn off soft stops G1 X-9.5 F6000 ; Go to X=-9.5 at 100 mm/sec G92 E0 ; Reset extrusion distance on new tool G1 E50 F90 ; Extrude 50 mm of filament at 1.5 mm/s on new tool M211 S1 G92 E0 ; Set current extruder position to 0mm G0 F10000 ; Increase feed rate before next travel. EXTRUDER END G-CODE ; End Extruder 1 G92 E0 ; Reset extrusion distance G1 E-5 F5000; Retract 5 mm G91 ; Switch from absolute positioning to rela