First of all I have to say I love TinyPortal. I can't thank you enough, you saved me from having to use phpBB or IPB.
The problem I have is as follows:
After clicking the collapse button, the blocks disappear but the main content does not stretch to fill the page. However, after collapsing the blocks and then going to another page, it will be stretched.
I use a modified SMF default theme. I basically just changed out the images and style.css.