Actually almost all the lightbox versions I have installed as well as "highslide" all have previous and next buttons that popup as you mouse over the zoomed photo. I have a variation of lightbox installed in my gallery2 that does this. I will have to look at the
js files and see how they are doing it. This is a must next step for the lightbox that is now included in photopost.
It is a waste to zoom into a photo then have to zoom back out and click to the next photo then zoom back in. Also, the version of lightbox that comes with photopost is missing cool feature such as... you have to click the close button to close the zoomed image. another version of lightbox allows you to click anywhere on the image or button. another nice tweak.
Photopost is all about photos and media and needs to step up the development of these cool zoomed features to further pimp out the gallery.
I guess I will have to hunt down where to set the "threshold" size limits. Is that a setting in photopost or tuck away in a lightbox file?