Yes, you will get an error 22 if both limits are active at the same time. We do not use the LD command, as it is specific to the Accelera controllers only.
What you could do it use the Notify commands from the RefAll button script to send your disable LD commands to the controller when the home operation starts and the re-enable LD commands when the home operation stops.
Change the script to something like this:
Notify( 3000 ) ' disable limits for the X, Y and Z axes.
DoButton( 24 )
DoButton( 23 )
DoButton( 22 )
DoButton( 25 )
Notify( 3001 ) ' enable limits for the X, Y and Z axes.
DoOEMButton(133)
DoOEMButton(134)
DoOEMButton(135)
Then in the plugin config Notify tab, add some Galil commands to ID 3000 and 3001
3000: LD 3,3,3
3001: LD 0,0,0
But... you will still have problems jogging off a limit switch if you hit one during normal operation. So you may want to add a button to your screen (using screen4) and do a similar disable limits Notify call so that you can move off the switch.
Steve