Hi,
the item that can match "exactly" with:
http://www.yoursite.com/index2.php?option=com_rss&feed=RSS1.0&no_html=1
Is the following:
^/index2.php\?option=com_rss&feed=RSS1\.0&no_html=1$
Notice that I used to specify that must start with (^) and end with ($). Also, I've escaped the question mark (\?) and also the dot (\.).
If this doesn't work, a reason could be another "matching" item with a lowest order. In case of problems, you could export a dump of redj table, and send me a PM at info(at)sistemistica.it.
Best regards,
Luigi