I also observed that the issue didn’t occur a few times in a row after freshly starting Seamly2D today, but then it started after maybe 3-5 times of good exits (step #3 above). After the crash occurs and I start Seamly2D again, the error occurs consistently.
Here’s the file I am using in my reproduction steps. basicpantssloper.val (5.0 KB)
Any of the tools use the same dialog method. There were issue with the Variables and History dialogs that use a different method, that I hopefully addressed with the Mac ver. Thing is I don’t have access to a Mac so I’m in the dark when it comes to testing.