BuddyPress.org

If you are using a page template that is not the BP activity or blog posts page then you will have to edit a file. In the plugin folder go into the themes/default and change the file front.php code

/*
Template Name: Home
*/

To match the name of the page template you are using.

If you are just using a plain WP page then you’ll have to hold on a bit until I work out forcing a front page regardless of what is chosen in the wp admin.