Snail tracks on the cured resin

Surface is smooth but has what looks like snail tracks is usually a direct result of not fully mixed resin. The ratio may be correct but the hardener is not mixed correctly. Picture in your head that part A as being white paint, while the part B is black paint. If you add the black into the white and partially stir it then you will get streaks of black within the now mostly grey paint. If fully mixed then you would have grey paint only with no white or black visible. When stirring your epoxy, scrape the sides because that is possibly where the streaks are coming from.