Collision help

Hi,

Im trying to make a little game in my spare time, I tried using the CDK with the help of Candadian on here I got a mostly working collision setup but it was full of bugs.

I want to make the image attached. I would like it to be flexible enough to use it again and be able to make a level editor. I can make a simple grid based collision detection set up with just square shapes but the rotated/irregular object in the middle of the illustration does pose quite the problem.

Any help would be greatly appreciated.