I don't appear to have that option on the qSelector webpart. what version of QWP is that on? I think we are using 5.0
the problem with using session variables on a drill is that the drill is not particular to the qListview part, the parameters are part of the previous page(s) and when I try to use qConnector as filters on the same web page, either the session variable is a step behind the selection, or (if I try to use connections) I get "No provider Schema" errors.
so far, moving to session variables within my application has had mixed results. when working from the top drill, where people might filter before drilling into an edit page, it's all fine. When I have come from a page to the current page, my drill is in the form of http parameters not captured by session variables at present (unless I put a load of hidden qSelectors on the drill page) so to go to an edit page from the drill page means I can't use the drill mechanism of charts, since they don't populate session variables, and populating qSelectors from http parameters isn't workable as part of the drill up/down.