Russell,
Many real tracks can be substituted for the ones that BB has in a specific style. In RB when you click on generate real track the whole list comes up so you can experiment with different ones that match your tempo range if you want. Be sure to use swing with swing and even with even etc. I use the programs in a very similiar way to Noel. The "threading the soloist" imo means finding nice little fills that fit your song. I'm sure Noel will answer your other questions.

Realband is a very good program that is still relatively new so I expect it will continue to expand with more features as all other daws have over the years. I would advise you to start with it and grow with it. I don't feel like I've scratched the surface with it yet but I sure have fun.

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