Donny, I will open up the PA4X and see if what you are asking can be done. I actually think it can. I'll let you know.
In other words, you want to be able to push Songbook title and have it open up with, for instance, STS 3, instead of 1, right?
I'm re-thinking this a bit, Donny do you want STS 2 to open with Variation 1 or STS open to let's say STS 3 with variation 1? If that's the case then I don't believe it can be done.