I have an UltraTimelineView with appointments in it. Lets say, I have these three appointments for 1 owner:

A1: 08:00 AM - 12:00 AM

A2: 1:00 PM - 5:00 PM

A3: 8:30 AM - 9:00 AM

So the output will produce 2 "rows" of appointments. In row 1 there is A1 and A2. In row 2 there is A3. Hope you can still follow ...

Now, I start dragging A3 to the right. As soon as A3 hits the gap between A1 and A2 the appointment jumps to row 1. There is my problem: I don't want that to happen. I want it to keep the initial Y position of the appointment.

I haven't found any properties related to that, so I tried the DrawFilter. In the GetPhasesToFilter Method I hooked up the AppointmentUIElement in the BeforeDrawElement Phase. For testing purposes I offset the AppointmentUIElement for 10 pixels (Y) and return true to keep the internal drawing routine. This don't work: The appointment isn't drawn or only a part of the border is drawn. It is somehow fully drawn as soon as I lift the mousebutton (I am still in the drag'n'drop operation) AND move the cursor at least 1 pixel. But the appointment isn't drawn completely. A border with a width of 1 pixel is missing. Its not the outer border of the AppointmentUIElement, but I think the inner border of the EditorWithTextDisplayTextUIElement of the AppointmentUIElement. 

So, is there a way to keep the Y position of an appointment that I drag and drop? (I use IG v10.3, Visual Studio 2010, C#)