Thank you for all your help. I got my scripts to work by using  -onChange=>'document.location..' and refreshing the page with a manually set query string. However, now, everytime the user selects a new pop-up menu, the page needs to be fetched afresh and more than the time to compute, it is the refresh time that makes the whole thing look really slow.

The only way I can see of speeding it up is by using Javascript as adviced in the previous posts. Trouble, though, is, my data structures are fairly complex and after looking at the documentations for Data::JavaScript and Data::JavaScript::LiteObject, I could not quite a figure out how I could transfer data and how I could be using them in JavaScript. In fact, I thought, Data::JavaScript::Anon was probably more suited to my needs. But the documentation isn't very explantory and I could not find any good tutorials or examples. I am new to Javascript as well; if any of the monks could help me by providing pointers to documentation, tutorials, examples or just advice, I would be extremely grateful.

Thanks,
Ashish