cubase has an automation feature which allows for this, among other real helpful things like adjusting volumes on the faders during the song, mute out entire tracks, and then back on again. there is a "read" and "write" button at the top left of the mixer panel. this is the automation. play around with it. it can be erased and you can start over if necessary. turn on the write button, and while the track is playing, activate the desired effect at the appropriate time, and then back off again, the automation will record the event. turn off the write, button, then turn on the read button, rewind, playback, and you should hear what you're looking for.
TBM