Nice feature. Here are two suggestions. An option to make the left / right arrows invisible or almost transparent. Once the width is set, it is easy to estimate where the sensitive area is. Otherwise the arrows are a bit distracting after a while.
The other idea is to use the screen's full width to define the sensitive area, regardless, if it is inside or outside the actual image.
Because otherwise, especially when using vertical formats, the point to aim at will be in a different place, as compared to the horizontal formats, which also are narrower that the full 16:9 format most of the time (used to be 4:3 or 3:2 formats). I think this would be the easiest way to click though the images.
We'll make the arrow cursors less obtrusive in the next update, see what you think.
With your other idea - actually it already works this way (it's based on the width of the window, not the width of the image) - so you can click there to go to next/previous already, but the cursors aren't currently shown unless the mouse is over the image. We'll make it so the cursors are shown in all cases.
Hmm, right. I don't know, how i got that impression. I think, you're right about the arrow thing, that made me think, i always have to bring up the arrow first to make it work.