I also find that this seems to catch a lot of people out, having 1 pixel of difference between 99.99% and 100% is hard to see so everyone assumes its actually full.

Having a larger step over, or some other type of difference on that last .01% would help this a lot.

When loading my save from last night in [16.39], and walking by my rail stacker, all the signals were blinking back and forth as though they were in non usable locations, IE placed then a curve added, or placed on the ground away from rails. All my rails were marked as a yellow line and no division ...