Solved Mesh stopped working after Marlin 1.10 upgrade

Ok, so I was having no problems at all with Mesh bed leveling when I had Marlin RC8 (although I had other issues that the new firmware fixed), but now, after upgrading to Marlin 1.10, mesh leveling simply does nothing. I go through the mesh leveling process on the LCD screen like I always have, but when I start the print, the Z axis does not move at all to compensate for bed unevenness. Once the mesh leveling is complete, I run a M500, and I'm able to recall all the measured points correctly using G29. I tried rebooting the printer several times. I tried redoing the mesh bed leveling. I tried uploading the firmware to the printer again. Nothing I do is making the z axis follow the contour of the bed. I even tried significantly exaggerating the measured points so they vary wildly (for troubleshooting), just to make the z movements more obvious during printing, but no luck. Please help!

 

G21 ;metric values
M107 ;start with the fan off
G28 ;move X/Y to min endstops
G29
M104 S[first_layer_temperature] ;set extruder temp
M140 S[first_layer_bed_temperature] ;set bed temp
M190 S[first_layer_bed_temperature] ;wait for bed temp
M109 S[first_layer_temperature] ;wait for extruder temp
G92 E0 ;zero the extruded length
M117 Printing... ;Put printing message on LCD screen

Another one?? Great, I'll give it a try, thanks!

 

Damn it. The z axis still won't budge while printing, even after updating to 1.1.1
I have had one problem after another with this printer. I can never go more than 2 days without some issue happening.

 

So I discovered that every time I type G29, I get the following. It keeps saying State: Off. Is this normal? When I type M420 S1 it changes to State: On. But the z axis still don't move. And after I cancel a print, it changes back to State: Off. Is there another step involved with activating it?
I want to also mention that I changed MESH_NUM_X_POINTS from 6 to 4 in configuration.h. I don't think that would cause issues but I thought I'd put that out there.

SENDING:G29
State: Off
Num X,Y: 4,4
Z offset: 0.00000
Measured points:
0 1 2 3
0 +0.24000 +0.60000 +0.62000 +0.44000
1 +0.34000 +0.46000 +0.48000 +0.62000
2 +0.40000 +0.42000 +0.48000 +0.72000
3 +0.30000 +0.68000 +0.82000 +0.66000

 

Hmmm... Ok, so I added M420 S1 to my start gcode script right after G29, and mesh leveling appears to be working now... I never had to do this before, why now?