Click-to-Reveal widget crashing the application, corrupting file

I'm many hours deep on creating a project in Captivate. When I add a click-to-reveal widget to a slide and click in to customize colors and icons, the app crashes. Then it corrupts the file. I managed to restore a previous version and Save As, but each time I get to the point of adding that widget, the same message, "an unexpected error has occurred, which may cause captivate to behave unexpectedly."

An older discussion post pointed to issues when customizing states, but I haven't done that.

I cleared cache, reset preferences, to no avail. I am operating on Mac OS, using Captivate 12.6.0.63. Can someone please advise?