Google maps smooth scroll to anchor outside map when clicking on anchor link inside the map marker info window. Not tested...

gmaps.smooth.js

// This line is different
// it attaches a google maps listener that fires when an info window is opened and populated.
google.maps.event.addListener(referenceToInfoWindow, 'domready', function(){

  // scroll handler
  var scrollToAnchor = function( id ) {
 
    // grab the element to scroll to based on the name
    var elem = $("a[name='"+ id +"']");
 
    // if that didn't work, look for an element with our ID
    if ( typeof( elem.offset() ) === "undefined" ) {
      elem = $("#"+id);
    }
 
    // if the destination element exists
    if ( typeof( elem.offset() ) !== "undefined" ) {
 
      // do the scroll
      $('html, body').animate({
              scrollTop: elem.offset().top
      }, 1000 );
 
    }
  };
 

  // THIS IS DIFFERENT :) 
  // We're targetting the "google maps-style info window" element, and finding all links inside it. 
  $('.gm-style-iw').find("a").click(function(){
 
    // Everything else is normal.
    // only do this if it's an anchor link
    if ( $(this).attr("href").match("#") ) {
 
      // cancel default event propagation
      event.preventDefault();
 
      // scroll to the location
      var href = $(this).attr('href').replace('#', '')
      scrollToAnchor( href );
 
    }

  });
  
});