you can use power cms content on security assist protected pages, but you will need to edit the WA_CMS/WA_CMS.php file to corewct a conflict, see the following thread:
showthread.php?t=15730
to add a login /logout link, use the following code:
<?php if(!WA_Auth_RulePasses("Logged in to users")){ ?>
<a href="users_LogIn.php">Log In</a>
<?php }?>
<?php if(WA_Auth_RulePasses("Logged in to users")){ ?>
<a href="users_Logout.php">Log Out</a>
<?php }?>