GregValiant: What I find is this: If I use the gcode as produced, then the hot end fan comes on after the extruder comes to temperature. I generally get a heat creep clog that blocks the filament from ever moving again, as it has heat-set some distance above the bitter end of the teflon tube.
However, if I edit the gcode file and move the MM106 S191 as shown above, I get perfect flow, perfect part, no media starvation, etc.
I shall either make my own post process to set as shown above, or alter the Marlin code, which happens to be 2.1.2.1 (new release), and this is all on an Creality Ender-4 h-bot that happens to, otherwise, work perfectly using the new Creality 2.2 board, which replaced the original board. The original board poofed the y-driver when -> I manually lifted the Z-axis, apparently too quickly <--
And, of course, Creality no longer supplies anything Ender-4, or even acknowledges the existence of the machine.
By the way, I never had this heat problem using the prior board/Marlin (again, Creality would only say "here's the github URL)... I also have an Ender-5 Plus, which has an additional, from Creality, fan, on the hot end box.
I can also (via menu), set bed, hot end temps, and fan speed, and end up with a fine part, using the output direct from Cura.