its pretty simple to do. what presets on gross beat are you using?
1) insert gross beat fxs into mixer
2) right click the volume nob of
the gross beat insert on the right side and select "create automation clip" from the pop up screen
3) go to playlist, your new automation clip should be in the playlist
4) resize the automation clip to your liking, 4bars....
now you need to play around with the little bar inside the automation clip
when you right click on the line, you can make a break in the automation clip, and it adds a new point. you need to resize it so that the bar fits in the 4 bars your trying to work with.
the lower you put the bar or pionts, the lower you will hear the effect. if you raise the points to the top of the automation, the fx will be full blast.
so if you keep the line constant at the top then it should play threw the whole 4 bars, depending on the preset you may get different results but they all basically work the same.
if you want the fx to end suddenly at 4 bars then make the little points into a right angle or lower the point completly.... if you end the automation clip in a right angle i found that you need to extend the clip 1 bar or else it will play threw out