So what you're trying to do is put all the thumbnails from the album into the image page, along with the current image...
What I would do is save the $_zp_current_image in some backup variable, like $_zp_current_image_backup and then restore it after you've gone through the album loop.
In fact I do believe that's what I'll do to the album loop from now on, to make it restore the original current_image after it alters it...