I use Podfarm for rehearsing on a laptop in Pro Tools. Podfarm is too slow to load patches live. The only way I've automated the patch changes is to create a track for each different patch and load that patch on it. I then use the track mute automation to mute all the tracks except for the track with the patch I want to hear. This way it makes no difference how long the patch takes to load as they are loaded when you open the session. System resources might be a problem if you have heaps of sounds you want to use. It was okay for me as I only had about four sounds, one rhythm, one clean, one lead, and one effected sound for one song. I had all songs and backings loaded in the one session with markers between songs, and used the space bar to stop start. It's pretty awesome actually, you won't want to use a foot switch again.
