Exactly like that...

Any help would be appreciated.

Thanks.

AP

Hello. Where can I download the solution for this post? I'm having similar problem. Thank you

Thanks Marin, this is very helpful.

I'll try putting the pieces together this afternoon. 

It is all. I'm going to attach the full solution but right now I'm busy.
This sample produces the following result:

4. Drag and Drop
Drag and Drop replaces positions of two tile and we need to recalculate offset and height factors:
private void tv3_TileDragCompleted(object sender, TileDragCompletedEventArgs e)
{
  MyTilePane tile1 = e.DragElement as MyTilePane;
  MyTilePane tile2 = e.TargetElement as MyTilePane;
  if (tile1 != null && tile2 != null)
  {
    double t;
    t = tile2.VerticalOffsetFactor;
    tile2.VerticalOffsetFactor = tile1.VerticalOffsetFactor;
    tile1.VerticalOffsetFactor = t;
    t = tile2.HeightFactor;
    tile2.HeightFactor = tile1.HeightFactor;
    tile1.HeightFactor = t;
  }
}

3. XamWebTileView control template
Open your page in Blend, edit the XamWebTileView template to create a new style and replace TilePanel with MyTilePanel
the original line is something like this: <igPrim:TilePanel x:Name="PagePanel"
and the new line should be: <local:MyTilePanel x:Name="PagePanel"
Finally your code will look like this:
<igTV:XamWebTileView x:Name="tv3" RowsInPage="2" ColumnsInPage="3" 
Style="{StaticResource MyTileViewStyle}"
TileDragCompleted="tv3_TileDragCompleted"
>
<local:MyTilePane Header="1" Content="1" HeightFactor="0.5" VerticalOffsetFactor="0"/>
<local:MyTilePane Header="2" Content="2" HeightFactor="1.5" VerticalOffsetFactor="0"/>
<local:MyTilePane Header="4" Content="4" HeightFactor="0.5" VerticalOffsetFactor="0"/>
<local:MyTilePane Header="3" Content="3" HeightFactor="1.5" VerticalOffsetFactor="-0.5"/>
<local:MyTilePane Header="6" Content="6" HeightFactor="0.5" VerticalOffsetFactor="0.5"/>
<local:MyTilePane Header="5" Content="5" HeightFactor="1.5" VerticalOffsetFactor="-0.5"/>
</igTV:XamWebTileView>