Photoset Gallery option on Joe's Tumblr stack

I’m using Joe’s Tumblr stack here -

and I wondered if there’s any way to:

  1. Make the thumbs bigger when you’ve created a Tumblr Photo post with two or more photos
  2. Actually make this a ‘proper’ gallery, when using the ‘Photoset Gallery’ option - i.e. one you can scroll through when the lightbox is open.

Any input from someone in Joe’s camp? @zeebe maybe? I’d appreciate it.

Many thanks