How to put time labels on TimeSlots?

Hi,

I have a radScheduler at https://mine.hourmine.com/c/pCalendar.aspx?pa=casey (navigate to next week if everything is gray).

Right now I am showing "available" text via a background image in the open time slots. But this is less than ideal. What I want to do is to show the exact time of that slot - like 9:15am, 9:30am on the slot itself and make it look like a button so that it is easier for the end user to know which timeslot are they booking.

I tried to use the following code in RadScheduler1_TimeSlotCreated() event

                Label lblStartTime = new Label();
                lblStartTime.Text = e.TimeSlot.Start.ToShortTimeString();
                lblStartTime.CssClass = "TimeSlotLabel";
                e.TimeSlot.Control.Controls.AddAt(4, lblStartTime);

But, I get a run-time exception that e.timeSlot.Control is null.

How can I do this? 

Thanks

nitin