I'll include this in the next release's readme, but in the meantime, if you want to have users show up in the WoL as 'In the "Chat Room"' then do the following:
In /languages/english/online.php (you should do this for every language you have if you have more than just english)
Find:
$ubbt_lang['previewsig'] = "Previewing their signature.";
Add After:
$ubbt_lang['chat'] = "In the \"Chat Room\"";