Ian the M3 and other Mcodes run in the VB side. IF you call any macro it could be VB releated
That should have read Gcode/VB interactions(;-) At a certain Ver time line large delays started to appear in Gcode/VB. Pre V.019 things ran very well and predictable. After that things took a lot of revamping to even run much less be reliable.
BUT that is just my findings.
(;-) OK I must have been absent one day at school WHAT is E1P0/1?