I do this with my stitching software, what program do you use to stitch with and I might be able to help? and even though krpano will allow you to set a start point I also prefer to do this when stitching.

I just check out your rig and it appears it creates a cylindrical image, not a spherical image, so I guess I can't help. but am still interested in the answer.

For the zoom, change maxpixel from 2.0 to 1.0.

Primarily I use autopano giga from kolor, and everything else as a backup for the ones that just won't stitch. ptgui gives good contro; over horizon and start point, but never tried adjusting a pano after the stitching. For what I assume you want to do, I would look at panotour or panotourpro. They use the krpano viewer and the xml syntax works in both krpano and panotour. They have a demo, try it and see if it does what you want.

The examples here help, but I find they assume you have an idea or basic knowledge to begin with so the learning curve is rough.

What are most of your images about and the extended use? Also if you have an image that you can describe what's wrong, or what you want done, send to me and I will play with it. Then tell you what I did to fix it it. I will send you a 'private message' with my email address.