Crash!

Today at 12:21 PM

I tried to apply my tool "fl_SwingTriplets.lua" to the second staff of this score.
NWC crashes just after my tool is finished.
As far as can tell, it's not my tool to blame but it's a bug of NWC.

While investigating, in some cases instead of the unhandled exception I got the "Pure virtual function called" message.

I think there is very little I (we) can do, beside using some obvious workarounds.
It's just for the records... or for the next version 3.