Nearly there now

I've built a forum in which I have used Data Bridge extensively throughout, and I have used the cookies toolkit to create sessions to which I have then used the show region utility to show and hide buttons based on a users logged in status, and all is working fine. What I need to do now is create the ability to do three things:

1. If a user's details exist in the database, but they have allowed their membership to the website to lapse, then I need to disable their ability to post in the forum. How?

2. If any user visits a particular thread that is meant to be locked to replies, how do I lock the thread?

3. Currently, all of the forums are open to public display, but only two of them need to be locked to logged in members. How do I achieve this?

I have got all the columns in the DB ready to be used in some manner... e.g.: if the thread is locked, then I have an INT column in the DB set to 1.

I guess I need to wrap the insert reply buttons in a show if statement driven by a session variable, but I already have a show if on them if the user is logged in. I assume I need to protect the insert and update pages, but again, I have show if user is logged in wrapped around the whole form. I'm struggling to figure out how I can secure the site without locking out those who shouldn't be.

Have you got any advice for me please?