Another note-to-self – and maybe / hopefully somebody else might also find this note useful…
The problem: The Drupal 7 module “node gallery” installed just fine and is running well. Additionally I installed the Plupload module for drag’n’drop and multi-file upload functionality – but no upload form / no upload option at all is actually happening.
Solution: there is a misleading detail in the readme.txt that comes with the module – or actually in the file structure / naming that comes with the module Plupload:
The installation instructions in readme.txt suggest that you need to upload the file plupload.full.js – but at the suggested location there is instead the minimized version of that file plupload.full.min.js.
sites/all/libraries/plupload/js/plupload.full.js vs. sites/all/libraries/plupload/js/plupload.full.min.js
The module will perfectly work if you first rename the file. So all you would have to do is remove the “.min” from the file name and upload the file – and everything is fine. The module works as intended and there you’ll have your drag’n’drop- and mupload functionality.