gustywinds,
This thread has some discussion about how to make Joomla and phpBB share a database (required for connector to work).
www.joomlapolis.com/component/option,com_joomlaboard/Itemid,38/func,view/catid,34/id,13901#13901/
The connector itself installs just like any other CB plugin... go to the admin side... then go to Components - Community Builder - Plugin Management... from there you can install a component in the area near the middle of the page height... should be an area titled something like install plugin. Select the file by pressing the browse button and selecting the zip file in the file open dialog. Then after double-clicking or pressing ok.. you can press the upload & install button. The plugin will publish itself upon upload.
To change parameters of the plugin go to the admin side then select Components - Community Builder - Plugin Management... then click on the plugin titled "phpBB Connector" this will take you to a screen where you can adjust the parameters of teh plugin... v. 1.0.2 only has a few options to mess with... note the patches you mentioned earlier for fixing "remember me" logins and for helping to transfer larger user tables... just ftp those files over the desired files to install the patches.
The URL given at first shows how to install phpBB and setup the connector... Since your phpBB site is already running... I would suggest setting up a new phpBB install as per the URL... then using phpMyAdmin or similar database program copy the phpBB tables from the old setup to the newly setup version (overwritting the new phpbb tables)... then proceed on to sync'ing users.
Hope this helps,
Greg