Pretty, but unusable?
Am I missing something basic? The slide rule is bigger than the screen, so must be able to scroll entire sliderule with all scales (except vertical line cursor) locked together. For example, to multiply 2 times 4, line up upper x scale 2 above lower x scale 1. Lower x scale 4 is not on screen... must be able to slide the whole slide rule over to the 4 without moving the center slider with respect to the outer scales. Can't do it. Needs a "lock center scales" button or somesuch.
Edit: I tried the Masayuki Akamatsu version and it works flawlessly (although with fewer scales). Simple solution: when moving the rules, the slider should move with them. Please fix!