Three Levels Deep on one screen?

I have a database with three files. Tickets, proposals, and proposal line items. A Ticket can have many proposals. a Proposal can have many line items. Withing a proposal, there are categories, which i have created with tabs. I'm using the "isfronttabpanel" to set an unstored calc as the primary key. On one screen in tickets, I show a list of all related proposals, next the the proposal you want you click view, which sets another key, this lists that proposal data. Now you click on a tab within that, and another key gets set based on the tab you're on. The data below in the portal doesn't seem to "refresh" correctly unless I go in and out of the record, or go to layout mode and back to browse, or some kind of mechanations. I have enclosed the file... maybe someone can take a look at the tickets screen. When I set the category field normally like with a drop-down, the relationship works correctly, but not with the unstored calc as part of a key. Any ideas?

focus.zip