Well it's a bit buggy, but pretty neat that you got this working! Pretty neat through it sizes Hammer to take up the space that the game doesn't.
Trying to use -noborder does not work well, it locks the Portal 2 window size. To avoid crash while quitting, close the Hammer window, not the game window. Also I have noticed that re-compiling an open map will cause the thing to crash.
THERE IS NO MOUSE LOOK! LOL
Turns out Hammer's "Move Engine 3D View to Hammer View" actually does the opposite.
The model browser is now black, UNFORTUNATELY it is also affected by the game resolution you set.Full size massive image view
Here you can see it respecting my dual monitors and a dynamic model that I added and "sent to the game"
I think we are missing some tools, the "Default Layout" button does nothing. It also seems that Foundry is a "tool module"...one of many?! Pluuuuuugiiiiinsssssssssssssssss