Ah, this is not surprising. The parsing system does not include entries for user-bound terms, so when it searches for possible matches, I presume that it is not finding anything for that term? Is that what you are seeing, or is it that you *do* get a selector for the custom word, but upon saving, it seems like the binding has come undone?
Yea, that's what I figured. Unfortunately, it would be a significant amount of work to get this working (for what I am guessing is a rather limited set of users). I'd love to get it done at some point, but probably not in the near future.
Okay, so not supported. I’ll remember that, but for other users, it might be a good idea to remove the add sentence link until such time as it becomes available.