I have this design downloaded as well. I will wait and see how the $7 metal one I ordered from alexepress for 1.75mm.
After reading about the new ultimaker geared extruder I have started reading up on versions out there. I'm not in a big rush since I have the other on its way.
I got my relay today so my bed heater is working awesomely!
I'm still using mattercontrole to build gcode since I'm still working out the kinks with cura. I also like that I can control the printer.
I'm busy printing parts like lcd case now I'm up and running. I have an old spark plug gap tool which I have found to be excellent for bed leveling.
I also found a nice gcode that helps with the level process by moving the head to each corner and pausing. I enhanced to to my liking and will put on my google drive later. Pausing does not seem to work on lcd controller from SD card printing so you may need to use MC for it.
I'm not sure if I will continue to pursue the UM2.1 code or not. I did notice the UM Original seems to use standard ramps and lcd so perhaps this is a better path than I have been taking.
My other option is to add in a function for filament change in the standard Marlin build.
Or use google. Doh.https://github.com/MarlinFirmware/Marlin/issues/3765