Galleria Folio theme: thumbnail display not restricted by height setting

Hi, following the instructions given in this module's documentation, I've created a page following the 'Using Galleria with an image/media field in a node' directions. I want the gallery to display using the Folio theme, but the gallery thumbnails don't display within the container width/height settings I specify in the Option Set configuration.

I've attached 2 screenshots for your reference - one showing my module config settings, the 2nd showing the actual page where you can see the thumbnails load in one long column. I thought the images would load horizontally across the width, then wrap onto new rows once the width restriction was reached?

Then, once the height restriction is reached, can I include a pager to access additional images, or would I need to create the gallery using a View to achieve this?

FYI, if I change the theme setting to 'Classic' the gallery display does adhere to the width/height settings.

I'm relatively new to Drupal, so I hope I'm missing something really obvious... but this has me stumped and I'd love to get it working ASAP.

Here is a link to the page: http://www.terracorptanks.com.au/gallery

Thanks in advance.