What I am trying to accomplish: 10 percent increase scale transformation of a rectangle via Silverlight storyboard animation.

What I currently doing: While in Expression Blend 3, I created a rectangle, created a storyboard, and created the scale transformation. The preview looked correct because the increase in scale begins in the middle of the object. When I run the project the scale transformation begins at the top left. Is there some piece of code missing?

Here is my current code:

<UserControl
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Class="TestingGroundsWebsite.MainPage"
    Width="640" Height="480">
    <UserControl.Resources>
        <Storyboard x:Name="RectangleAppear">
            <DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="rectangle" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleX)">
                <EasingDoubleKeyFrame KeyTime="00:00:00" Value="0.1"/>
                <EasingDoubleKeyFrame KeyTime="00:00:01" Value="1.1"/>
                <EasingDoubleKeyFrame KeyTime="00:00:02" Value="1"/>
            </DoubleAnimationUsingKeyFrames>
            <DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="rectangle" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleY)">
                <EasingDoubleKeyFrame KeyTime="00:00:00" Value="0.1"/>
                <EasingDoubleKeyFrame KeyTime="00:00:01" Value="1.1"/>
                <EasingDoubleKeyFrame KeyTime="00:00:02" Value="1"/>
            </DoubleAnimationUsingKeyFrames>
        </Storyboard>
    </UserControl.Resources>

    <Canvas x:Name="LayoutRoot" Background="White">
        <Rectangle x:Name="rectangle" Fill="#FFE80000" Stroke="Black" Height="75" Width="76" Canvas.Left="227" Canvas.Top="167" RenderTransformOrigin="0.5,0.5">
            <Rectangle.RenderTransform>
                <TransformGroup>
                    <ScaleTransform/>
                    <SkewTransform/>
                    <RotateTransform/>
                    <TranslateTransform/>
                </TransformGroup>
            </Rectangle.RenderTransform>
        </Rectangle>
    </Canvas>
</UserControl>

Thanks