LitePublisher has Lightbox gallery. You do not need to create thumbnails. LitePublisher create thumbnails when you upload image. Just click upload button in post editor to add image.

LitePublisher uses an advanced gallery jquery prettyPhoto.

I uploaded several photos to demonstrate gallery. click on the thumbnails to view a large photo. These photos I made in Zaraysk kremlin (russian castle between Moscow and Ryazan).

you can change any settings of humbnails in the admin panel onOptions/View page.