Ron Rennick

The WP/WPMU author link from the <code>the_author_posts_link()</code> template tag on the blog will link to the author’s buddypress member profile instead of the author’s posts page.
This plugin will only affect blogs where buddypress is activated sitewide. It will function the same in either the mu-plugins folder or in the plugins folder and activated sitewide.

BP Blog Author Link

This plugin changes the blog author links on a buddypress site to link to the author's buddypress member profile.

Enej Bajgorić

ctlt-dev

oltdev

An easy way to modify the css globally on your site.
As an admin you are able to edit the css from the front end.

Improved Simpler CSS

Add the ability to add css to your existing style sheet.

BP Blog Author Link vs Improved Simpler CSS