there seems to be a bug that when you change the duration in batch mode, the remaining batches of the generation will be executed at the new duration, but scored at the old one
measurements on the floor / steps / obstacles could be good to have.. like numbering the obstacles, or a simple ruler on the floor for running, perhaps numbered steps?
I read the section on not limiting muscle length in your FAQ, but I thought of another approach to the problem: You could perhaps have muscles tear when stretched beyond X times their initial length, and remove such creatures from the gene pool?