I installed WordPress a few times and could not get Multisite to work properly, with or without BuddyPress.
It appears that when a new site is created, no template is applied to the site, even though the setting indicate that there is a template applied. I also tried manually changing the template in the settings, and it did not make a difference.
Also, the link at the top of the page to create a page either went to a page that did not exist or went back to the home page.
Thanks for all your work on this project!