Hello Arcticigloo ,I also have a sharp 2412 , G33 does not apply to threadmilling its more for single point thread cutting.
It looks like your cuting a 1 inch dia thread don't know the pitch.
The program looks wrong line N65 will place the cutter well outside the 1 inch circle. Also theres no Z while cutting therefore no movement.
Also the cutter should climb out of the hole G3 insted of G2
Lets say you want to threadmill a 1x 10 tpi . 5 deep thru hole with no cutter comp. and no lead in or lead out .
(JOB 2 THREAD MILLING 1 X 10 TPI)
(TOOL #3 0.3720 THREAD MILL )
G0 90 G54 X0 Y0 S1000 M3
G43 H3 Z.1 M8
G1 Z-.650 F50
G3 I-.314 Z -.550
Note G3 I-.314 Z -.550 cuts a full circle while Z rises 1 full pitch.