Hi Ted,
Check out Band in a Box. The pg music site should have a heap of demo's and tutorial video's.
In the last few years it has moved away from just midi styles to a mix of audio/midi and straight audio styles.

Basically you just type in a chord progression , choose style , Mark where you want fills and ending.

I don't actually use it a great deal, but I have had the program since about 1990 and I upgrade it every couple of years or so. The progress over the years has been amazing.

http://www.pgmusic.com/bbwin.features.htm

I'm reasonably certain it will help you with chord progressions, I haven't used it in a while.

The pg forum is very helpful

I used to actually have biab midied to my korg ie I used to type my chord progression into biab and it synced and played the progression using the arrangers style instead if it's own.

It's a function biab has had for years, the ability to sync an arranger to it's chord progressions. Hoping I kept a note on the settings I used to make it happen.