Here is a fast, easy solution. When you click a note to add an expression, search for the z shape. This is not to be confused with either of the turn ornaments. If you find it, check to see if it is shape #122. If you don't see it, you can create the shape and playback will not be impacted.
I'll see if I can get on later and provide a more detailed set of steps. Or, you can use the Finale Manual to find out how to create 'new' expression shapes.
Hope this helps.
iMac i7, OS 10.8, 10.9, W7
VDL2.5.5, Finale 2010-14
Kontakt 4-5, various other soft synths