Midi-controls-menu
It is possible to insert extra midi-control-events for effects like sustain, chorus, vibrato and reverb with the MIDI-controls menu
You can add your own control events by modifying the instrument definition file
From the menu use [Edit|Tools|MIDI-event|Control change] to pop up the control-events menu where you can make your selection.
Based on the part's MIDI-channel the correct MIDI-event is inserted into the part.