[Plugin: WordPress SEO by Yoast] customizing title on categories

Hello
will this plug in work if the theme already has an seo build in
the one thing mine will not let me do at the moment is the change the title on the categories it will let me do all the other pages.
i like your plugin but i just wanted to check that it will work with my current theme i have the elegant estore theme which has a build in seo but it is limited.
Thnakyou Matt

http://wordpress.org/extend/plugins/wordpress-seo/