Full circle arc with offset problem?

Your error is line N50
You cannot activate cutter comp in a G2/G3
So
N30 X100 Y42 (random location)
N40 Z20
N50 G1 G42.1 D3.17 X109.2826 Y40.1466 F400.
N55 G2 X117.2813 Y40 Z2.6 I3.9993 J-.0733
~
rest is fine.

Try this

G0 G54 G90 G91.1 X0 Y0 S10000 M3
G43 Z1 H1
G01 Z-1 F80
G1 G41.1 D5. X15 Y5. F200
G3 X0 Y20 I-15 (J0) *zero values not needed in incremental arc center mode
J-20
X-15 Y-15 J-15
G1 G40 X0 Y0
G0 Z1
M30