Sure this could have to do with changing the php.ini file to php5.ini
if you change back does it fix the problem?
for the 404 error, it looks like the profile page is set to redirect to the users_LogIn.php page instead of users_login.php
find:
WA_Auth_RestrictAccess("users_LogIn.php");
and replace it with:
WA_Auth_RestrictAccess("users_login.php");