Add plugins..
Step one - download plugin.
Step two - unzip
Step Three - read the readme.
Step four - copy the .py to the extplugins folder and the .xml to the extplugins/conf folder
Step five - add a line in th eplugins section that follows the format of the line above.. I.E. (this is a example) <plugin "name xlrstats config @b3/extplugins/conf/xlrstats.xml"/>
Step six - restart b3 and profilt
Some plugins have more steps like the geoip one, but the steps are in the readme.
As for restricted access... see:
http://forum.bigbrotherbot.net/xlrstats/restricted-access/