When you use windowed zoom it rarely will happen that the edges fall on nicely round timestamps. Most of the time the result will more like this:
Because PicoScope divides the range in 10 divisions you get the weirdest division markers, like in the screenshot: 75.34 ms, 80.65 ms, 95.95 ms, etc. These are completely meaningless and useless. Wouldn't it be better to have division markers at more rounded numbers, in this case at 80, 90, 100, 110 and 120 ms? I don't care that there aren't exactly ten of them, nor that the window doesn't start at a division marker. The "500ms/div" indicated in the toolbar isn't valid anyway. Maybe you can use divisions of 80, 85, 90, 95, etc ms, in order to have closer to ten divisions.