htaccess Elite

hi , this is my first topic in this forum and I'm really pleased to found a forum specialist in htaccess.

actually i was asking about how to make "pafiledb script" links more seo, and for who didn't know about pafiledb script , you can look at this page :
http://www.phparena.net/scripts.php?script=pafiledb

and this is alive demo for this script:
http://demo.phparena.net/index.php?demo=pafiledb


I was hope to make urls instead of this:
/index.php?act=view&id=1
/index.php?act=category&id=3
/index.php?act=search

to be like this:
/category/category1/topic name or topic id.html
/category/category1/
/search/


any help will be appreciated.