Hi Timber,
Sorry about the delay in getting back to you but I somehow missed your response last week. If you hadn't followed up, I would have missed this completely. Anyway, I confirmed what you said about not being able to see anymore details in the expression builder once you've gone 3 levels deep. I even created a blank database with just 3 forms and a textbox in the innermost form and I could not see the textbox either in the expression builder because the innermost form shows up with a different icon and no details.

I know in Access 97, you could only go 2 levels deep but my understanding was that you could go 7 levels in Access 2013. I will continue to research this but right now you'll just have to manually enter the reference to your control the long way. So if you want to refer to WorkHours from a query , you would have to type in:Forms![frmRptReportDate]![subfrmRptTeam].Form![subfrmRptTeamWork].[Form]![subfrmDetProductiveHours].[Form]![WorkHours]
Hopefully I or someone else will have a better answer later on.
Ron