6
The rule with XOOPS custom user groups is you can give them more - but not less - than registered users. So you can give a custom group 'Demo' access to a block that ordinary registered users cannot see. However, you cannot hide a block from the 'demo' group without hiding it from the 'registered users' group too.
The second problem is that wherever the demo user's name is shown - e.g. in the 'who's online' block, the user can click the link and edit their profile, including the password.
Best solution I can think of is to add a conditional statement to the Smarty template for 'edituser.php' so that the 'change password' field is only shown if the user is NOT in the user group 'demo'.
A thread is for life. Not just for Christmas.