Rhino 6 crashes ONLY when editing a dimension?

Strange thing has started happening regularly a modle I have working with for over a year.
In a layout when I edit a dimension the program simply shuts down, does NOT autosave and when I go back into the same file nothing has changed and all the edits since my last manual save are lost. Seems to have started since another recent windows update.

Any ideas why this might be happening ?


Hi -
Does this also happen in a new file from a factory-default template?
Please run the Rhino SystemInfo command and copy-paste the result here.