knownasilya

Looks like the following works so far (replace var show and var hide):

// Function to show the loading bar
      var show = function(){

        return this.each(function(){
          if($(this).data("loader") !== undefined){
            $(this).data("loader").showLoading();
          }
          else{
            init($(this), settings);
            $(this).nimbleLoader('show');
          }
        });
      };

      // Function to hide the loading bar
      var hide = function(){
        return this.each(function(){
          if($(this).data("loader") !== undefined){
            $(this).data("loader").hideLoading();
          }
        });
      };

This is around line 85 in wp-content/plugins/smugmug-for-wordpress/external-code/nimble-loader/jquery.numble.loader.js

Also having similar issues, have been able to activate the plugin with SmugMug, but unable to import smugmug galleries. I have tried mileandra’s solution, but no luck. Investigating further.