your reply, refairing to the old post is an immense help! If i understood it right: the foam chip blocks are for sitting higher-so i could use something else if i don't have them? i could e.g. put some layer between the lower legs and the sitting bones to sit a bit higher-would that give a similiar effect to the foam blocks? and then for the items to place directly behind the knees and then on the calves-i can use towels?