When you render\export a track with a sidechain effect, you need to bear in mind that it becomes possible for the rendered effect to become out of sync with the sidechain source. That’s the problem with rendering sidechain effects, and the very problem that was mentioned in the first tip on this topic.
Therefore, when you use this approach it’s very important to keep the original track around and easily accessible so you can re-render it when the sidechain source track changes.
To do this, I’ll generally create a rack for every device in the track I’m rendering and then turn off the rack’s activator switch after exporting it.
This is just an easy way to reclaim all of the CPU power used by these devices without having to turn off each device separately.
When it’s time to re-export the track, I can just switch the rack back on and I’m ready to rock.