To be fair, a function that is not working and a function that is not fired at all are 2 different scenarios in many cases :)
Anyway, when you say that the function is not working, I assume that even if you add a standard alert in that function, it is not fired at all, is that so? If yes, you most probably have a second RadWindowManager on that page. In such case, you need to take into consideration the following:
1. All RadWindowManager's functions (radopen, radalert, radconfirm, radprompt, GetRadWindowManager, etc) are always using the first rendered RadWindowManager on the page.
2. Every RadWindowManager "knows" only the RadWindows that are declared in its Windows collection.
This means that if you have a RadWindow2 as a standalone control OR declared in RadWindowManager2, and you use something like radopen(myUrl, "RadWindow2");,
radopen will use RadWindowManager1 and will open a new RadWindow with the settings taken from RadWindowManager1.
To avoid that problem, when you have multiple managers on a page, you need to get a reference to the correct RadWindowManager first and then call its methods.
var manager = $find("<%= RadWindowManager2.ClientID %>");
I hope this information helps. If it doesn't, please open a support ticket and send me the code for the masterpage and the problematic content one, so I could check them.
the Telerik team