Inter-App Audio on multiple tracks

Before I do a lot of digging, can you help me with this? As of now, I’ve found a way to listen to the track I want while playing those I want too. Simply choose CH1 as the input to that track and not the others. In this way I’ve created a project. But when I go to adjust the relative volumes of the tracks I find that nothing works, in other words the mixers don’t adjust the volume of the tracks (except for Track 1, which scales all tracks together), nor do the box adjustments for individual tracks. A related question is how to introduce dynamics with a slider during or after recording a track, I haven’t tried to map a slider to a specific track volume yet, but want to do so. I’m sure these are very common things people want to do … Thanks, RAK