Creating a Structure variable in blueprint causes editor to crash on re-open

I’ve got a structure variable:

It’s got some other structures nested within it (if that’s relevant):

My engine is opening fine to take these screenshots, and I have a blueprint where the first structure is used:

Everything works fine, EXCEPT if I CREATE A VARIABLE of that structure (i.e. to save the loaded data table row), the engine WON’T open if I restart it!

Things I’ve tried:

  • Refreshing and recompiling every blueprint in the entire project
  • Resaving every blueprint and structure and asset in the entire project

What is going on?? Is there a way to solve this?