Created Unassigned: ajaxToolkit:ToolkitScriptManager and UpdatePanel [27660]

I have a Master / Detail pages project and uses UpdatePanel to avoid the "flickering" of the screen when changing detail pages. This works very fine in version 4.5.7.0607 of Ajax Control Toolkit with a ToolkitScriptManager in the Master page. However, when I upgrad to versionor 4.5.7.1005 or 4.5.7.1213 the whole project starts to "flicker" when I change to a Detail pages or just click on a Button on a Detail page. If I remove the ToolkitScriptManager and use the standard ScriptManager then the project crach with the following error codes:

0x800a138f - JavaScript runtime error: Unable to get property 'UI' of undefined or null reference

$create(Sys.Extended.UI.CalendarBehavior, {"button":$get("ContentPlaceHolder1_cmdCalendar"),"id":"ContentPlaceHolder1_ajxCalendarExtender1"}, null, null, $get("ContentPlaceHolder1_txtNoteBookDate"));

I use Visual Studio 2013. I have explored most of the suggestions on the Forum but no one gets close to solve the problem. What to do? Is there a problem with the ToolkitScriptManager and do I just have to wait for a new release?

Lennart Hoglund