This is probably more to do with how you’ve setup WordPress rather than BuddyPress. BuddyPress redirects based on what WordPress thinks is the right URL for the site, it does not hard code https, but simply get the site address from WordPress.
Buddypress works for me as you indicate, except for the pages of each group that always redirects me to http: //
I have open_ssl installed with a certificate. I have a wordpress latest version and buddypress latest version, I have configured multisite. I tried to put the domains to https: // and to http: // I always redirected the group pages to http: //
One page of group is
http://redols.caib.es/c07000000/grups/lectors/
All I can say is that BP is using the following WordPress function to get the url for the group:
get_home_url( bp_get_root_blog_id() )
So your WordPress thinks the home url is http
Looks like you’ve not configured ssl correctly, Firefox won’t let me visit your site.