If your timing isn't off to begin with, when you line up the lines on the new belt with the notches in the cams (and clamp them in place) and then line up the double line with the notch on the cam gear (and clamp it in place) everything SHOULD snap into place when you pull the pin on the tensioner.
I think I pushed on the belt near the tensioner to see if everything would line up before pulling the pin just to make sure it was all lined up right.
I think you mentioned downloading Barts write up, but if you haven't I would strongly suggest getting it and reading through it a few times to understand everything. I used Bart's write up exclusively, and read through it MANY times before I ever turned a wrench. I tend to be a visual person so the pretty pictures that Bart included were perfect to help me understand what was going on. I don't consider myself to be particularly mechanically inclined, but I can follow instructions (fairly well) so the write up was like a "Timing Belt Replacement For Dummies" for me.
Hope some of that helps. I'm happy to answer any other questions that you have, or if you want to talk it through I can pm you my phone number.
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong, it usually turns out to be impossible to get at or repair."
-Douglas Adams, Mostly Harmless