Thanks Jazz, that manual has a bit more info than mine.

I will test out the system later today when I get dressed, it is 5am here in Australia and cold too.
The project I am working on is a plasma cutter that has a standalone THC with a DC motor, so I only need to use X and Y axis with Mach3.
Because the table is wide, I will be using two stepper motors and will need to slave Y and A together. I might have some homing and limit issues to deal with later.
I have already changed the Ref All Home button to allow homing of only the X and Y
DoButton( 22)
RefCombination( 10 )
I guess I will find out if it works for real later, it works on the screen OK.
The THC has a DC motor and is fully automatic, but I will still need to lift and lower when setting a job up, so I will use real push buttons to do that. There are not enough inputs and outputs available on this board to allow some keyboard macros to control a couple of extra relays needed for that part (unless it is possible to reassign some unused pins maybe?)