'Paste role' causes SWAT to freeze

[HairMachine]

I'm following the tutorial for SWAT at http://storytron.com/Tutorial/t-a-09-enriching-storyworld.html#/

When I get to the end of this section, I can copy the role "punchee", but, after I navigate to the verb editor for 'hit with' clicking "Edit -> Paste role" causes the program to lock up. The window cannot be closed or interacted with at all.