Hi,
First the easy question - to export single tracks just solo them when you do the export.
Or is this the easy question - to thank someone, click the thumbs up icon at the top/right of their post. Hover over it and it gives you a handy tool-tip.
The Midi volume question is trickier… Perhaps you need to look at the midi chase options because it may not be chasing while looping? Or look in the midi part and check the volume messages? Or is it a problem with automation, it can be a bit flaky sometimes?
But, you’ve been a bit sparse on detail here so this is guesswork, if you provide some more detail on what you’re doing then people can hopefully be more specific.
Mike.