Posts are closed by admin. The reasons that have for doing so are various, not least because either they feel the thread has reached the end of its useful life or there has been a transgression of the forum rules. Usually they wont give the reason, even when asked. Thats the rules of this forum.
If you delete photos from your allocation they are deleted from memory as they "belong" to you. Again, thats the way it works.
There are other ways to post photos by linking to photos on 3rd party host sites. That way you can have as many photos as you want without eating into your forum allocation.
Again, its just the way the forum has been set up.