i would like to amend the code for the single post byline to show authors name, only for certain categories. As well, i would like the authors description/bio at the bottom of these posts.

I have two main categories in my site. One is "projects". the other is "articles". I need the articles to feature authors, but not the projects.

Would you know where/how i could amend the code to do this, or is there a plug-in i could use.

thank you once again. This is the best theme ever.

take a look at ATO->Edit POST/PAGE INFO ITEMS you can set what ever you want (of the options) in what ever section you want. If you look at the lines just about 'KICKER: Homepage' you will see you can even add a php IF statement to put in the logic to control what shows when

okay...
i am still learning ...
the syntax doesn't seem right here.... but how would you work with this?

<?php if ( in_category(15)) %author-link% ?>

try it like this
<?php if ( in_category(15)) { ?> %author-link% <?php }; ?>

This works great. Thank you so much.