BuddyPress.org

Odd that that plugin doesn’t make clearer provision for the logo, however if it can specify a stylesheet then simply copy the WP ruleset and change the background call on the h1 a to your image and path?

If you want a very crude, rough and ready approach you could use this dropped into your themes functions.php, it’s not a particularly clever method though but works.

http://pastebin.com/N64tzcFD

You could add a few other override rulesets to the embeded styles if you wished, but I would keep it simple otherwise a more formal approach would be better.