Thanks Gerry, Stirling,
Yes that was what i tried before but after adding the macro to the INIT line, mach would not start again, I had to revert to a backup to get going again then aborted trying to get this working that way, I will try again tonight.
Another oddity, after messing with editing the macropump macro, Mach seems to get a bit pissed and does odd things like starting up code with no M3 so no spindle, MDI and M3 and you get the script compiler error message, restart Mach and its happy again. Done this a few times now - is it a bad idea to edit the macro pump file while Mach is running?