It works well. There was a small typo:
add_filter( ‘bp_xprofile_global_tables’, ‘buddydev_filter_profile_tables’);
Should be: add_filter( ‘bp_xprofile_global_tables’, ‘buddydev_global_profile_tables’);
What about avatar images and cover images. They currently write to the uploads folder of each site independently. Is there any way to write them to the main site only so that they can be used on any site?