@ElmoC, I have this start gcode for Simplify, hope it work for you
M140 S[bed0_temperature] ; set bed temp no wait
M104 S[extruder0_temperature] ; set extruder temp no wait
G28 ; home all axes
M116 ; wait all temps
M98 P/macros/CleanNozzle ; clean the nozzle
Not familiar with the M116 command. Will look into that. Thanks.