I think there definetly is an issue here because I created a new page with nothing on it but the navigator control and the TimeRangeSelectedHandling event does not fire:
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="Appointments_Default" %>
<%@ Register Assembly="DayPilot" Namespace="DayPilot.Web.Ui" TagPrefix="DayPilot" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<DayPilot:DayPilotNavigator ID="DayPilotNavigator1" runat="server" TimeRangeSelectedHandling="JavaScript" VisibleRangeChangedHandling="JavaScript" />
</div>
</form>
</body>
</html>