I just stubbed my toe on this one this weekend when I tried to pop up a found set in a list view in a small window...
When you open a new window, every table occurrence in your system get's a new found set in that window. The found sets in your current window and any changes you make to them do not affect the found set's in the new window. To see the desired record or records in the new window, you have to either perform a find or use Go To Related Records to open the new window.
Does "go to related records" work when not using portals? Since I'm all within the same table, I presumed I couldn't use this.
... what's driving me crazy is that the same script works in some layouts and not in others....
Regardless, I'll give it a whirl, and see what happens. I was thinking I could add some script steps that involve copying the original ID # into a variable, then opening a new window and performing a find with that variable #.
I did say that it's either GTRR or performing a find. The find you describe is exactly what I had in mind.
You can use GTRR without any portals as long as there is a relationship that will work.
If you want to learn more about GTRR, see this link: The Complete Go To Related Record