Anyone know how I can get the physics engine to behave more like this game :
http://www.addictinggames.com/puzzle-games/redremover.jspLike how it feels very solid, and the blocks feel pretty sturdy when they are falling etc?
I have been messing around with the physics in my game, and it seems no matter what combinations of heaviness and friction etc.....it's always just so so so wobbly

(I have bounciness set to 0 on everything btw)
Even just stacking up around 5 or 6 blocks (snapped to the tile grid) is difficult without them falling under their own weight, or wobbling around and eventually toppling over....and if I drop anything on them from any kind of height at run-time, it's pure carnage.
Anyone got any tips for making really nice, solid blocks?