I've created page with Views, which is displaying gallery (image fields).
I've set the path to node/%/gallery.
do not use node/%/.. as your path, this will disturb the default routing system.
change the view's path to gallery/% or something.
if you want to keep this url, register a local task like here How to add a local task tab to node view?
and in this page callback you can display the view with views_embed_view, in this case you will remove the path of the view, or change it to a test-path.
but still, the alias with /gallery needs to be registered too !