Glad you like 'em.Neat!
Front/back placement depends on the relationship between the subject and the edges of the frame. Output from ZS is computed to place the midpoint of the subject at the same depth as the frame. This can be changed arbitrarily as the images are cropped. Generally I prefer to avoid stuff sticking out of the screen very far, so my crop-to-taste images end up mostly behind the monitor whether I think about it or not. It's kind of the "object in a display case" look, where the monitor is the front of the case.Both of those last two seem to stick out off the monitor. Mostly...they seem to sit behind where my brain thinks the monitor is.
--Rik