Google Website Optimiser

[haggul]

Does anyone have any experience with using the Website Optimiser with dynamic pages?

I have a category page that I have created multiple versions of, e.g. Category1.asp, Category2.asp and so on... Each of these displays the same sort of content but in a different format.

Each page takes a parameter in the querystring of ?CID=X where X is a number that represents the category.

How can I setup the Optimiser experiment to switch between the actual pages but retain the actual querystring. At the moment under certain circumstance the google script just tries to redirect off when it feels like it.

Hope that makes sense - basically just trying to work out wheich format of the same pages converts best.