Check it out....

Sorry if that was a little complex. I've had that very problem in the past and that was one solution I've used. It's really not a big deal if it just takes a second to load.

I really think Lightbox is one of your better options for displaying the images. There are a few options out there. Some of the ones I know are a little more complex. Probably your best solution is a Windows app (unfortunately). If you can run Windows applications on your Mac, I would suggest checking out Visual Lightbox. I know the frustrations of Windows-only applications as a Linux user. If you need any other help let me know; I'll gladly do what I can to help you out. Even if you just need someone to test something. It's coming along nicely.

Visual Lightbox: http://visuallightbox.com/