I found out how to produce reduced scores (I've been mistakingly calling them condensed scores . . . condensed scores are different) in Overture SE! This is probably available in other notation program as well, if you do some fooling around.
A reduced score is simply a way to save space by only showing the notation for the instruments that are being played. For example, if you've writing a symphony, it would waste space to keep showing the woodwinds section if they don't come in until half way through the symphony or something. Many scores you find in bookstores are done like this. It can save a lot of paper!
Here's how to do it in Overture SE: select Score -> Hide/Show Staves... then check the "AutoHide" button and drag the number of systems up to it's maximum (which depends on the length of your piece). Hit "okay" and you're done! I don't know why I didn't see it before . . .
If you've already discovered this . . . you should've told me!