yes, yes, I had done that! only difference is that CSMIO has no port numbers, but only PIN. In my case it was PIN 1.
The relay connected to output1.
The relay is activated / deactivated only by Mach4 with enable / disable.
the m210 and m211 macros had no effect on output1.
on the CNC Italy forum I found this macro, can it be useful?
I attach the file.