I had already done that and could find no settings that where different to a default profile. I spent about 3 hours trying to track it down and finally found why the problem occurs. As you know I have some fairly heavy customisations. One of which is the M3/4/5 scripts. These scripts check for errors in starting the spindle and if an unrecoverable error occurs aborts execution of the rest of the script by using a M2. Here is a really simplified script showing the issue. Put this as your M3.gcode and when you load a gcode file no toolpaths will be displayed.
Code:
O<error1> if [#4100 NE 3] (dlgname,Spindle Error, opt=1)
(dlg,Failed to set spindle speed, typ=label, x=20, w=280, color=0xffa500)
(dlg,Response size wrong, typ=label, x=20, w=280)
(dlgshow)
M2
O<error1> endif
M3
My guess is when parsing to generate the toolpath it sees the conditional M2 and stops parsing at that point.
Cheers
Simon