Portal within a portal?

I haven't been able to do this one yet. Am I beating my head against a wall trying to figure this one out?

Probably.

The coroner had to fill out a death certificate

If you define a layout as belonging to a Table Occurrence, then a portal on that layout will be filtered through the TO. Of course, it has to make sense, ie., be a subset of that TO.

There is an example of this on the NewCentury web site, http://www.newcenturydata.com, named "gtrr_multi_hop.fp7"

It's not really a "portal in a portal," and each portal on the layout would have to be a subset of the TO; but it gets you somewhere; especially with the ability to create and place a new window(s) to show these.

You can also do some squirrely things by overlapping offset portals. But I wouldn't, except for fun.