When I run mesh bed level it measures 9 points as usual but only spanning half of the bed. Whereas before the 9 points covered the whole bed. Neither does it move to the dump bucket at the start of a print like before, the head only travels half way across the bed and stays there. The only thing I've changed is the zsteps to 400 because of the lead screws, and i reset the eprom after installing the .hex by going to restore failsafe before making any changes as recommended in the wiki. When i move Y to 100mm it only goes to 50. It's a new rumba, same hex file for the firmware as before. Any ideas, have I missed something ?