I'm using Cura 4.6.1, and a brand new Ultimake 2+.
I'm having similar issues when printing via USB. I did learn that setting g-code flavor to Marlin helped a lot.
The main problem I'm having when printing VIA USB is the printer does not execute the g-code end sequence which leaves the extruder & bed heaters on and does not return them to the home position.
Also, G-code commands issued from the Monitor window are very slow to execute or do not execute at all.
BTW: I'm trying to setup a dedicated desktop 3D printer server (Its easy to turn disable sleep mode) for
