EGR Gasket Leaking

I have a 75 mm throttle body with a 75 mm BBK EGR plate. I used the supplied EGR gasket (for the tb to the egr plate) and it is leaking. So now I am going to try to create my own gasket using gasket material I picked up from the parts store. Has anyone done this or have a better way of fixing this?

Also I have a question on why there is extra gasket material that hangs over the coolant valleys (see picture below).

View attachment 378419

Thanks
 
It's there to hold the center ring in place. Without it, the gasket would be 2 peices and you would never get the center ring in the correct position

No I understand that it needs support for the center ring but on my EGR plate there is only one side of the plate has the metal surface for it to lay on (there is only one because there is a coolant supply and coolant return).

Anyone have any cures for leaking EGR gaskets?