Need Help! Zero point problem

Hello.

I do not know if i this is the right place to post this thread.
But here is my problem: When i run a program i created on mastercam the zero point seams to move a little every time i restart the program.
Does any body have a idea what the problem might be?

It Starts and end like this:
%
O499(SEKSKANT 35,5)
T8 M6
G0 G90 G56 X-5. Y35.75 S3200 M3
G43 H8 Z2. M8
G1 Z-1.364 F3000.
Y30.75 F1000.
G3 X0. Y25.75 I5. J0.
G1 X10.075
G2 X17.263 Y21.6 I0. J-8.3
G1 X27.338 Y4.15
G2 X28.45 Y0. I-7.188 J-4.15
X27.338 Y-4.15 I-8.3 J0.
G1 X17.263 Y-21.6
G2 X10.075 Y-25.75 I-7.188 J4.15
-
-
-
-
-
G2 X-28.45 Y0. I7.188 J4.15
X-27.338 Y4.15 I8.3 J0.
G1 X-17.263 Y21.6
G2 X-10.075 Y25.75 I7.188 J-4.15
G1 X0.
G3 X5. Y30.75 I0. J5.
G1 Y35.75
G0 Z100.
G0 Y150.
M30
%