I ran yours and actually had the same problem, really befuddling me.
…then omfg. Apparently something in the recent changes does something, I don’t know what, with how it reads comments. All I did was remove the space before, and everything after and including the ; in your header and footer, and it ran correctly. Reverted the change to have the comments back in; it began running high again. Snapmaker; the hell?
So yeah in your lightburn config, try using this header (added a G90 for safety after the homing):
M106 P0 S255
G28
G90
G53
G0 Z30.6 F6000
G54
G92 Z0
G0 Z300
G53
G0 X0 Y0 F6000
G54
G92 X0 Y0
M3 S0
and footer;
M5
G0 Z330 F6000
G0 Y350
G28
NOTE TO EVERYONE ELSE, REMOVE MY NOTES FROM YOUR HEADER. 