My apologies. I wrote the subject heading before I wrote the rest of it. After further experimenting, I don't think it was the numeric suffix at all. Perhaps it's just that the answer to the disambiguation menu doesn't work. And if you ignore the menu completely and just start typing commands, it gets in a real mess. Do you remember we had a couple of games with this issue in the last jam? And Adam Sommerfield struck it in at least one of his YouTube videos of jam entries.
I've removed the large branch from this room, so I no longer get the disambiguation menu.