Quote - CSS is not the problem! I don't have any CSS scripts.

If your user CSS is empty, that confirms that it's the default layout that's the problem.  

Quote - This problem only happened recently.

Same with the forums, some layout change that was made broke things.  

Quote - I have always had my options set to open all in large size. Renderosity caused the problem so they should fix it!

The recent layout changes include fixing the size of HTML elements in such a way as to make the layout broken by design with that option set, due to the table and cell sizing specified in the HTML.  

Quote - ... until it gets fixed.

I definitely wouldn't hold your breath