Is it possible to automate adding a comment denoting the current layer in the g code when the G code changes the Z height? Is there a setting for this in Slic3r or is there an option to add custom labels?
Under output options you could add a post-processing script that divides the maximum layerheight of the sliced object by the layer height and then have it be added as a comment after each layer. But I am not sure how to do it. It is definitely possible though.