Can't believe you don't have this ability (if you do, please let me know how to do it):

I want to be able to grab a measure-line handle, drag it left or right, and have the music, in the same system, to resize itself PROPORTIONATELY, all the way left to the left end of the system, and all the way right to the right end of the system.

As it is now, I'm forced to manually try to drag and size each measure in a system if I want to effect the above request. This seems to me a very obvious ability that ANY music notation program should/would have!