5
You have to also change it in your theme.html so that the center-right blocks loop is not part of the same vertical container with the center-center (or main column). If you're table based, the center-right loop has to be a different column (not row). If you're doing it with divs, the center-right loop cannot be contained in the same div in which you have your main (or center-center) stuff.
That's on the assumption that you want to recycly the center-right blocks for your second right column.
The site you're referencing uses a table. That seems quite feasible. So you have in your theme.html something like:
left blocks loop |
center and center-left block loops and main content |
center-right blocks loop |
right blocks loop |
You can size and arrange it with the css file. If you want to design it tableless, then I wish you the best of luck, and a lot of patience.
Four columns looks like a challenge, at least if you want to have it liquid. Fixed width should be easy.