can not get tiled gallery to work

I am trying to display image thumbnails on a page in a tiled format and when the user clicks on each image, it gets expanded into the original size, similar to the following link (scroll to the middle)

http://artbiz.ca/using-jetpacks-tiled-gallery/#.UfPJRpyLNfM

But I just can not get the images to display properly – the thumbnails are not packed together and has a lot of white space in between. Also upon clicking the thumbnail the image does not get displayed (I set the action to image instead of file). Is there anything else that i need to do?