In this update we are introducing a block damage system to Medieval Engineers. You should no longer be able to destroy a stone wall with just one hammer/tool hit. We also added damage decals so you can easily see which blocks have been damaged.
Additionally, this patch contains a new lockable rope drum block for catapults so you will no longer need to reattach the rope after each firing. It can also be useful for gates (opening/closing) or pulley systems (such as elevators). The rope's minimum/maximum length can be manually set.
https://www.youtube.com/watch?v=ltu16zj9pR8
Full list of new features and fixes: http://forum.keenswh.com/threads/7360637