Hey Arima, I think that works for the Mouse object, but I don't think it works for sprites.
I found a reasonable solution though, it involves creating an "anchor", which is a sprite with the anchor behaviour on a layer you want that is set at pos: 100,100. This is used to determine the scale of the canvas, if we turn it into a percentage:
This will give something like 70 or 100% depending on monitor size, so you can multiply this to other uses of LayerToCanvas to make it consistent across all displays, I just jumble it all together though:
(100/LayerToCanvas X("Layer",anchor.X,anchor.Y))*LayerToCanvas X("Layer",sprite.X,sprite.Y)