Right now theres a problem with bipedal designs and that is that you have to be realy lucky to achieve walking. There should be some kind of a system for the user to set the basic movements the creature should preform for a certain task. For example the user would move the joint to prefered locations and set the basic movements for the creature to learn from.  Or there would be a more advanced system for setting each muscle to contract or expand to preform the basic movement. That would bring more to the game. I bet this is realy difficult to make, so dont expect the developer to program these features (not hating, I do know this is very time consuming and difficult to program).

as this can improve the evolution, it does ruin the hole purpose of the game. the game is fun because you see something you have created learn how to walk just on the knowledge that moving right is its goal. the game takes patience. You just dont make something and wait 5 generation to see if it works and than scrap it because it didn't. think about it this way does it take 5 days for a baby to walk when it is born, no so you need to give it some time. you want to have it on 30 sec generation to give it time to think in each generation and wait for a while. a good idea to do is before you go to bed make a creature and let it learn and by the time you wake up it will be walking. so just be patient and let it learn and its not luck. i bet almost everything you make will walk if you give it time. here is a creature i made with 1500 generation