BuddyPress.org

I have both a dev and live BP site running with BP_ENABLE_MULTIBLOG and the BP social network works fine on all sites/blogs. So, if it’s not working for you on the sub sites (with or without the patch), then you have another issue somewhere (conflicting plugin, etc.).

Assuming the patch is added to BP, I will be writing a simple plugin that will segregate BP by WP network.