Some questions about HTML Template Flexy

Hi people, I'm new to Seagull and Flexy. I'm trying to fix a project another programmer started. I have 2 problems right now: 1. How do I add parameters to the URL? I tried to add a "page" parameter, by appending "/page/{page number}" (such as "/page/3") to the URL. The original URL looks like "my.domain.name/index.php/dream/dream/action/cat/?DREAMS=2cd73545e5191345d5143dcbdf20e4fa&/1/id/12", and with my page number it is "my.domain.name/index.php/dream/dream/action/cat/?DREAMS=2cd73545e5191345d5143dcbdf20e4fa&/1/id/12/page/3", but when I have function _cat(&$input, &$output), $input->page is still null. 2. in the template, {if:pages} works fine, but {if:pages[#previous page#]} does not. I receive a parse error. How do I check if an array element exists? Thanks! Uri Even-Chen