Re: https vs http for bbPress URL
https is *not* the default protocol when installing bbPress. What gives you the idea that it is? Was a field pre-filled with a https:// value? Did you navigate to the installer from an https page? Or is the link to bbPress coming from an https page?
Just change it to http:// unless you have an SSL certificate and require the security.
Oops – edited after _ck_’s message below.