The Authenticate User Server Behavior allows you to set values from the user table into session variables. If it's not present yet, you can add an entry for the user name on step 3 of the Authenticate User Server Behavior wizard. From there, you'd simply need to drag from the Bindings panel the user name onto the page.
The log in for SecurityAssist uses session variables, and the length of time that a session stays "alive" is based upon a server setting, and that would depend on what server language you are using. Some servers may lock this down and not allow changing of the values.
For ASP:
Default time is 20 minutes. You can use something like the following, to set the session timeout to 45 minutes:
<%
Session.Timeout=45
%>
session timeout to 45 minutes
For ColdFusion:
The default is also 20 minutes. To change this, you have to change the sessionTimeout attribute of the cfacpplication tag, something like the following to set your timeout to 45 minutes:
<cfapplication name="ApplicationNameHere"
sessionmanagement="Yes"
sessiontimeout=#CreateTimeSpan(0,0,45,0)#>
For more info, please check the Adobe LiveDocs site for ColdFusion
For PHP:
What I've seen is that the default is 24 minutes, and this is set within the php.ini file for your server and can be changed via PHP code if the php.ini file is not locked down by a system admin.
<?php
$garbage_timeout = 2700; // 2700 seconds = 45 minutes
ini_set('session.gc_maxlifetime', $garbage_timeout);
?>
But again, this may be locked down.
HTH