Here’s another thread about the same problem:
https://intfiction.org/t/conversation-rules-vs-6f95/1540/1
I can’t remember the details, but I think you can avoid the problem by being careful about how you create your tables.
In the meantime, perhaps someone should ask Eric Eve to update his extensions with some hints and examples about avoiding the problem. I found an email address for him at Harris Manchester College and wrote there, but I don’t know if it’s current.