So I have got the latest version of Marlin up and going on all 3 of my printers. Marlin 2.0.5.3 and I also got the latest firmware installed on the MMU2S. 1.0.6. I am still not getting past the initial priming to get me to my first print. I have seen some people using a prime bucket and I think I am going to make one for this printer. It promises to save filament over building a prime tower and it definitely saves space on the build plate.