Index: lams_central/web/includes/javascript/authoring/authoringMenu.js
===================================================================
diff -u -r93dd27fb26bddbd5549a04530b4ee88036961f06 -rc1a5012654a6a505a5f8cec825c080f4d7f56a78
--- lams_central/web/includes/javascript/authoring/authoringMenu.js	(.../authoringMenu.js)	(revision 93dd27fb26bddbd5549a04530b4ee88036961f06)
+++ lams_central/web/includes/javascript/authoring/authoringMenu.js	(.../authoringMenu.js)	(revision c1a5012654a6a505a5f8cec825c080f4d7f56a78)
@@ -547,8 +547,11 @@
 					dataType : 'text',
 					success : function() {
 						// open preview pop up window
+						var left = ((screen.width / 2) - (1280 / 2)),
+							// open the window a bit higher than center
+							top = ((screen.height / 2) - (720 / 2)) / 2;
 						window.open(LAMS_URL + 'home.do?method=learner&mode=preview&lessonID='+lessonID,'Preview',
-									'width=1280,height=720,resizable,scrollbars=yes,status=yes');
+									'width=1280,height=720,resizable,scrollbars=yes,status=yes,top=' + top + ',left=' + left);
 						previewButton.button('reset');
 					}
 				});
Index: lams_central/web/includes/javascript/common.js
===================================================================
diff -u -rccfaf7a9ef3cf04f1647bcb16ff673ca8cfc5952 -rc1a5012654a6a505a5f8cec825c080f4d7f56a78
--- lams_central/web/includes/javascript/common.js	(.../common.js)	(revision ccfaf7a9ef3cf04f1647bcb16ff673ca8cfc5952)
+++ lams_central/web/includes/javascript/common.js	(.../common.js)	(revision c1a5012654a6a505a5f8cec825c080f4d7f56a78)
@@ -20,7 +20,10 @@
 	if(wd && wd.open && !wd.closed){
 		wd.close();
 	}
-	wd = window.open(url,title,'resizable,width=1152,height=648,scrollbars');
+	var left = ((screen.width / 2) - (1152 / 2)),
+		// open the window a bit higher than center
+		top = ((screen.height / 2) - (648 / 2)) / 2;
+	wd = window.open(url,title,'resizable,width=1152,height=648,scrollbars,top=' + top + ',left=' + left);
 	wd.window.focus();
 }