Subform with Autonumber headache

[RxExec]

I'm trying to figure out why when I create a new record in my main form the autonumber doesn't update in the subform. I created a quickie test DB (dbBWorks) because I couldn't believe it wasn't working, and sure enuf it worked and updates as expected but I would really like to know why my project DB(dbAFails)fails. Also, the main form opens with a blank autonumber record...is that an expected behavior? Really appreciate your input and suggestions.