OK, I managed to reproduce the crash.
I will call this a bug and report it to NI.
Please refer to the attached mod of the original llb.
Open the vi "Waveform Graph with Zoom_Cursor SelectCrash.vi".
The new "crash button" on the FP lets you determine if you want the VI to crash or not.
I noticed that crash occured while I still had the mose down so I started trowing away code until the problem went away.
I appears that
If
the previous active palette tool was zoom
and
the mouse down event is firing
and
you set the active palette tool to "2".
then it crashes.
Omit any of these criteria and no crash.
In my example that is how I control if it crashes or not.
Ben