Cookie help please

Running local on xampplite. Integration is working and blocks are showing correct data from vbulletin. Creating a new user in drupal does create that user in Vbulletin. However I am having no success with log in between products. I have been working quite awhile with cookie and other settings, but I am not having success with log ins sharing between products. I have a feeling from reading other issues and forum posts that it is a cookie issue.

Firefox is showing cookies from both are appearing in localhost, although vbulletin cookies have "bb" prefix (even though I changed config.php from cookie prefix: "bb" to "" - I'm not sure why the prefix still shows as bb in Firefox), I'm not sure if the cookie prefix matters.

I have tried clearing cookies and restarting and clearing caches but nothing changes.

Logging in to drupal creates 2 cookies:
has_js
SESS421aa90e079fa326b6494f812ad13e79

Visiting forum creates:
bbsessionhash
bblastvisit
bblastactivity

Logging in to forum creates:
bbuserid
bbpassword

Setup:
http://localhost/drupal - 6.9
http://localhost/drupal/bb - Vbulletin 3.8.1

At one point, I replaced Vbulletin login and logout to direct to /drupal/logout and /drupal/user, but I suspect I was getting ahead of myself and I need to solve the basic issue first.

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On a separate issue, in /admin/settings/drupalvb, the box for "New User Options" default is "3415". What is "New User Options" and the variables allowed, and why is 3415 the default?

Thanks!!!