In the moonlight midi example that comes with note worthy there is a tril at a bar around 30 or so. How can I get one in my own work?
The trill symbol is available within the boxmarks font, which is available at the NWC Scriptorium (http://nwc-scriptorium.org/).
You can install this as a user font under page setup-fonts tab. You will find many useful musical symbols within boxmarks. To get a correct sounding playback for trills, you must also use a hidden staff, which is an exact copy of your visible/print staff, except that the trilled notes are written out as sixteenths/thirty-seconds, etc... The hidden staff is the one you want to play, while the visible staff should be muted. To see how this was done in the example, go to page setup-contents tab. You can do the same buy naming any staff you want hidden as "hidden" in the staff properties-general tab.
See https://forum.noteworthycomposer.com/?topic=916, https://forum.noteworthycomposer.com/?topic=348, https://forum.noteworthycomposer.com/?topic=523