session.setVariable vs scrape result variable

Hi there,

I'm trying to scrape an ASP shopping site page as my first challenge after going through the tutorials.
I've figured out you need to retain your asp session state thingies throughout so I'm assigning a ~@variable@~ to a portion of scraped data up front, then editing the properties of that variable and setting "save in session variable".
I'm then wanting to use that same variable to post to the next page to keep the asp session alive.

I've proxied from browsing to home, click dvd, enter search, click next, click details - more or less along the lines of the tutorial with the exception of including the home page to pick up the session states.

It appears that just referencing the variable in the post parameters using ~#variable#~ doesn't work. They come up null.
By this then I'm assuming each scrapeable page is effectively it's own session, and variables scraped during the session aren't global?

So - how do I pass them neatly from one to the other? I've tried reading the referer method, but my non-dev brain is battling to get to grips with it.
Is there a perhaps a tutorial like the existing one that includes maintaining the session states with this method?

The other avenue I'm considering is trying to pass variables with scripts, but then it means creating one variable for the scrapeable page to get the data, then creating a new variable for the next page and passing them to each other - is that right?

I'm evaluating enterprise version - awesome product :) - and I've done all the tutorials and read as many related forum posts as possible, but I just can't seem to get my head around this - any help much appreciated!

Kind regards,

Russel