Stitching

There's one in the DS2 modding compilation which I started last year but never completed.
http://www.siegetheday.org/~iryan/files/ds2_modding_resources.zip

It's by Talon and unfortunately the original seems no longer available online. The link from Siegenetwork doesn't work.

The compilation is a collection of html files with an index. You can find the stitching tutorial either by finding the file directly in the folder and opening it or by opening any of the other files and finding it in the index.

I hope it helps you. Its for DS1 but the procedure is the same in DS2. I've been able to successfully stitch regions together and its straightforward enough when you get your head around the basic principles.