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If you dont put your own M104 S0 M140 S0 right after the G28, cura will will insert them at 1st layer temps.
You will need to put the M104 M140 later in the start codes else cura will not heat the bed/extruder.
M104 S{material_print_temperature_layer_0} ; set extruder temp
M140 S{material_bed_temperature_layer_0} ; set bed temp
M190 S{material_bed_temperature_layer_0} ; wait for bed temp
M109 S{material_print_temperature_layer_0} ; wait for extruder temp
It is reddened because cura is warning you that a 0.4 layer height is too high for a 0.4 nozzle.
Ideally you should set layer height to about max 90% of nozzle diameter, so try 0.35 layer height.
Had this problem while printing a 3d plane, you need to turn the retract at layer change on then cura will use the extra prime setting at layer change(i have mine at 0.1)
If it is Marlin, you can disable endstop detection by sending a M121,.after you have homed the printer.
re-enable detection with M120
These can be added to cura's start/end gcode.
This could also be a problem with spurious interference from the stepper motors being picked up on the endstop wires,
what firmware are you using?
did you upload it to the controller or was it already installed ?