Re: BBpress not sharing login details
The way the guide suggests to do it is actually a good way also.
Delete ALL the salts and keys from your wp-config.php file, visit the Site Admin area of your WordPressMU install, and you’ll get a warning saying you need to add the salts, and it will auto suggest them.
Copy those into your wp-config.php file, and then copy those same keys, put them in your bb-config.php file, but put “BB_” in front of each key name.
Also don’t forget to put whatever the recommended cookie path settings are in each *-config.php file…
As those will determine which directory the cookies are for.