1) With luck someone can chime in with your exact combo and give you the numbers. Basically you want to line up your chain. The best way is to try different options, which gets real expensive if you aren't working in an environment where you can pull that stuff off the shelf. Both Harris and Spicer have these frames and parts for sale, and might be able to sort it out.
What I did was buy a variety of the parts from Nashbar in different sizes and try them on my bike. Their sealed BB was about 12 bucks at the time.
2) Don't know whether it maters which you use with bar ends. I am using the LX deraileurs in 8 speed.
3) Check this out:http://www.crazyguyonabike.com/doc/?...c_id=2720&v=1k
I am using half step and a front double myself. It depends whether the bike is specialized for touring.
"People (myself included) get all caught up in these tiny performance details that really don't matter that much. Your bike is going to be awesome. Repeat after me, "you're bike is going to be awesome." Now quit a fussin' and go ride it!"
Good advice. There is a big difference between what I think about on the road relative to my bike, and what I think about when learning on here. The view from the road is much more pragmatic. Though the choices one makes can be in aid of that also.