Hello everyone!

I am new here and have the following problem:
I want to create a procedure on a Fidia M1 controller in which I want to place a piece zero point from a pre-defined register.
The whole looks like this:
[...]
RG 04 -120. ;coordinate X
RG 05 -70. ;coordinate Y
.
.
.
ORIGIN 1

SET XM:04
SET YM:05
[...]

The last part (SET XM:04 SET YM:05) is the interesting part- what is the correct Syntax?
I already tried various versions without success.

Thank you in advance

Regards
michael