Plex.exe crashes when opening the panel which preview setting of the form.
Plex.exe crashed when trying to open a panel with ActiveX control of Crystal reports 8.5 registered.
If ActiveX is not registered on the PC, they can open that panel without problems.
This problem is because Plex r 7.2.1 does not support Crystal reports 8.5 ActiveX control because it is old.
We recommend upgrade Crystal reports
Additional note, Crystal Report compatibility matrix with Microsoft Visual Studio.