Hi guys! Not sure, but may be anybody help.
My rotary axis have 10000 ppr, or 27.77777777777778 pulses per degree. This is  G-code of my machine

G17 G90 G54 G49 G40 G80 G50
G21
M6 T1
M3 S4000
M8
G64
G1 A0.0 F10000
G0 G54 X0 Y0.0
G0 Y0

M98 P0001 Q120
G0 Y0
G1 X0 F3500
G1 A0 F10000
G0 X0
M9
M5
M30

O0001
G1 X0 F3500
G01 Y-1.65 F1000
G01 Y-1.88 F40
G01 Y-2 F18
G01 Y0 F1000

G91 A3 F10000
G90
M99

Subprogram is very simple. Problem is next: the software not correctly divide angle of rotary table (A). As result to end of program i have near 1.5 degree of error. Mach calculate position from table resolution with little error (2.988 on each movement in exchange of 3) but at the end of code returned to zero right. I trying to use variavles into code but nothing help. May be my math knowleges not enought. Anybody know way to write program right, that Mach calculate position not from last errored point? From axis zero point incrementally?
Thanks all!

If you call the sub 120 times then the error must be +/-3 if your steps per are set correctly.

The other thing the code is setting the A to 0 before the G54 is commanded so if its not a G54 zero to start with the incremental moves will keep it out of place.

The problem solved without Mach software and plugin. I run same code directly from KmotionCNC (machine controlled by Kflop). Rotary axis work excellent, no any errors, no problems with g54, g91 and so on..