One of my houses has an unavoidable issue with players potentially getting stuck. The return to start button can help with this but it would also be helpful to have a menu chat phrase "I can't move" that could be recognized by castle magic to try to get players out of potentially tricky spots and would hopefully become well known. I currently have a jump detector, thinking that stuck players may jump to try to get free, but it's hard to know what people might do.
Another phrase that would be useful is "I don't know what to do". This would help for giving hints or bypasses in puzzle or mazelike houses, potentially allowing players who can't proceed to continue touring the house.