Hi Oiliver,
its not a software fault at all. If you read the documentation about RFH it tells you how Mach does a dummy run thru the
code to the restart point so its modal are correct. It cant accommodate G31 because without movement such a code can
never complete.

The same documentation will tell you that there is another means of restarting Mach that doesn't require a dummy run but
just starts at the nominated line with its current modals. If the modals are wrong that's your problem.

Once I understood how RFH works and the preparatory move works I've used it without bother. You can too. I'll see if I can't
find the documents, I know they exist, I read them and that's how I know to correctly handle RFH.

Craig

Hi Oilver,
straight out of the manual:

6.2.7.7 Line Number
Line DRO is the ordinal number of the current line in the G-code display window (starting
from 0). Note that this is not related to the "N word" line number.
You can type into this DRO to set the current line.
6.2.7.8 Run from here
Run from here performs a dummy run of the part program to establish what the modal state
(G20/G21, G90/G91 etc.) should be and then prompts for a move to put the controlled point
in the correct position to for the start of the line in Line Number. You should not attempt to
Run from here in the middle of a subroutine.
6.2.7.9 Set next line

Craig
Like Run from here but without the preparatory mode setting or move.