BuddyPress.org

I’ve never used GA’s content overlay, so I can’t tell you the specifics.

Try clearing your internet cache / cookies to remove the site overlay setting.

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Member blogs are a different matter, since the member blogs do not use the BP theme.

You can try modifying this line:

add_action('bp_after_footer', 'bp_ga_analytics');

with:

add_action('wp_footer', 'bp_ga_analytics');

Then put the plugin in /wp-content/mu-plugins/THEGAPLUGINFILE.php to activate Google Analytics on all your WPMU blogs.