Hey. i found out that Simplify3D has update to 2.1.2 and implament an auto calibration for the grid 2.
I have an mbot cube with rid upgrade and got the position problem. so here is my start script that work for me.
; **** GRID II start.gcode ****
M73 P0 ; enable build progress
G162 X Y F3000 ; home XY axes maximum
G161 Z F833 ; home Z axis minimum
G92 X0 Y0 Z0
G1 X0 Y0 Z5 F833
G1 X-145 Y0 Z5 F3000
G161 Z F200 ; home Z axis minimum
G92 X-145 Y0 Z0
G1 X-145 Y0 Z5 F833
G1 X0 Y-240 Z5 F3000
G1 X0 Y-240 Z0 F200
G1 X0 Y-240 Z5 F833
G1 X0 Y0 Z5 F3000
G1 X0 Y0 Z0 F200
M132 Z ; Recall stored home offset for Z axis
G1 X0 Y0 Z25 F833 ; move build plate down
M132 X Y A B ; Recall stored home offsets for XYAB axis
M135 T0 ; load right extruder offsets
G1 X-100 Y-105 Z30 F2500 ; move to waiting position
G130 X20 Y20 A20 B20 ; Lower Vrefs while heating
M126 S[fan_speed_pwm]
M104 S[extruder0_temperature] T0
M133 T0 ; stabilize extruder temperature
G130 X127 Y127 A127 B127 ; Set Stepper Vref to defaults
G92 A0 B0 ; zero extruders
G1 X-120 Y-105 Z0.2 F1200 ; lower head
G1 X-95 Y-105 Z0.2 E25 F300 ; purge and wipe nozzle
G1 X-90 Y-100 Z0.5 F1200 ; lift
; **** end of start.gcode ****