I presume that when you say "When I attempt to use it in any axis or any jog mode" you mean that not matter what the jog step size is you always get this error. Is that correct?
This is likely some interaction between the two plug-ins, though it could be a timing issue between the Mach4 core, our plug-in and our device that is influenced by the VistaCNC plug-in.
I would like you to capture a debug log from our plug-in. The general instructions are here:
http://www.pmdx.com/PMDX-Forums/index.php?topic=97.0EDIT: When enabling the debug log - please enable the "Motion Info" level instead of the "Debug" level mentioned in the above link
After you enable the debug log, exit Mach4 then re-start it. Set the pendant to try and jog an axis. After you see the error message, disable our debug log (step 6 in the link above), create the profile package and email that to me at bob at this domain. Or you can post it here, though you will have to rename the file to a ".zip" extension instead of ".m4prof".
Bob