It is not possible within Juicebox to hide the main image and display only the thumbnails. It is also not possible to associate links with thumbnails, although you could use the Juicebox-Pro API onImageChange ( index ) method to listen for an image being changed (i.e. a thumbnail being clicked) to fire a function to then open a new web page depending on which image was selected.
Currently, the only automated method of creating a multi-gallery album in a single pass is to use the Juicebox Skin with jAlbum. However, it uses a JavaScript navigation tree (with text nodes, not thumbnails) to select the gallery to be displayed.
An alternative would be to use svManager. You would be able to create individual Juicebox galleries which would be listed (with thumbnails) on an index page like this sample svManager installation.
Please note that the current version of svManager does support Juicebox but the demo page has not yet been updated.