Just to update, it worked! I'm now improving it and creating custom art, will probably post a final version once I have it, this is how the code looks now. Thanks @faeran and @Retro808 for your help!
<UserControl xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:transitions="clr-namespace:Unbroken.LaunchBox.Wpf.Transitions;assembly=Unbroken.LaunchBox.Wpf"
xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
xmlns:cal="http://www.caliburnproject.org"
mc:Ignorable="d"
d:DesignHeight="360" d:DesignWidth="1920" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Style="{DynamicResource UserControlStyle}">
<!-- GRID DEFINITIONS -->
<Grid Height="360" Width="1920" VerticalAlignment="Stretch" HorizontalAlignment="Stretch">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="3*" />
<ColumnDefinition Width="7*" />
<ColumnDefinition Width="3*" />
<ColumnDefinition Width="3*" />
<ColumnDefinition Width="2*" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="5*" />
<RowDefinition Height="1*" />
</Grid.RowDefinitions>
<!-- GAME MARQUEE -->
<Image Source="{Binding Path=SelectedGame.MarqueeImagePath}" Stretch="Uniform" HorizontalAlignment="Center" VerticalAlignment="Center" RenderOptions.BitmapScalingMode="HighQuality" Panel.ZIndex="0"/>
<Border x:Name="Blackscreen" Grid.Column="0" Grid.Row="0" Grid.RowSpan="2" Grid.ColumnSpan="5" Panel.ZIndex="1" Background="Black" Opacity="1" SnapsToDevicePixels="True" RenderOptions.EdgeMode="Aliased" ></Border>
<TextBlock x:Name="MarqueeBackgroundPlatform" Visibility="Collapsed">
<TextBlock.Text>
<MultiBinding StringFormat="LAUNCHBOX_ROOT_FOLDER/Images/Marquees/Platforms/{0}.png">
<Binding Path="SelectedGame.Platform" />
</MultiBinding>
</TextBlock.Text>
</TextBlock>
<Image Source="{Binding Text, ElementName=MarqueeBackgroundPlatform, FallbackValue='LAUNCHBOX_ROOT_FOLDER/Images/Marquees/Platforms/Default.png'}" Grid.Row="0" Grid.RowSpan="4" Grid.Column="0" Grid.ColumnSpan="8" Panel.ZIndex="2" Stretch="Fill" RenderOptions.BitmapScalingMode="HighQuality" />
<Image Grid.Column="1" Grid.Row="0" Source="{Binding Path=SelectedGame.ClearLogoImagePath}" Stretch="Uniform" HorizontalAlignment="Center" VerticalAlignment="Center" RenderOptions.BitmapScalingMode="HighQuality" Panel.ZIndex="2"/>
<Image Grid.Column="2" Grid.Row="0" Source="{Binding Path=SelectedGame.CartFrontImagePath}" Stretch="Uniform" HorizontalAlignment="Right" VerticalAlignment="Center" RenderOptions.BitmapScalingMode="HighQuality" Opacity="0.5" RenderTransformOrigin="0.5,0.5" Panel.ZIndex="2">
<Image.RenderTransform>
<TransformGroup>
<ScaleTransform ScaleY="0.8" ScaleX="0.8"/>
<SkewTransform/>
<RotateTransform Angle="-20"/>
<TranslateTransform X="-20" Y="-20"/>
</TransformGroup>
</Image.RenderTransform>
<Image.Effect>
<BlurEffect Radius="50"/>
</Image.Effect>
</Image>
<Image Grid.Column="2" Grid.Row="0" Source="{Binding Path=SelectedGame.CartFrontImagePath}" Stretch="Uniform" HorizontalAlignment="Right" VerticalAlignment="Center" RenderOptions.BitmapScalingMode="HighQuality" RenderTransformOrigin="0.5,0.5" Panel.ZIndex="3">
<Image.RenderTransform>
<TransformGroup>
<ScaleTransform ScaleY="0.8" ScaleX="0.8"/>
<SkewTransform/>
<RotateTransform Angle="-20"/>
<TranslateTransform X="20"/>
</TransformGroup>
</Image.RenderTransform>
</Image>
<Image Grid.Column="3" Grid.Row="0" Source="{Binding Path=SelectedGame.Box3DImagePath}" Stretch="Uniform" HorizontalAlignment="Left" VerticalAlignment="Center" RenderOptions.BitmapScalingMode="HighQuality" Opacity="0.5" RenderTransformOrigin="0.5,0.5" Panel.ZIndex="2">
<Image.RenderTransform>
<TransformGroup>
<ScaleTransform ScaleY="0.8" ScaleX="0.8"/>
<SkewTransform/>
<TranslateTransform X="-40" Y="-20"/>
</TransformGroup>
</Image.RenderTransform>
<Image.Effect>
<BlurEffect Radius="50"/>
</Image.Effect>
</Image>
<Image Grid.Column="3" Grid.Row="0" Source="{Binding Path=SelectedGame.Box3DImagePath}" Stretch="Uniform" HorizontalAlignment="Left" VerticalAlignment="Center" RenderOptions.BitmapScalingMode="HighQuality" RenderTransformOrigin="0.5,0.5" Panel.ZIndex="3">
<Image.RenderTransform>
<TransformGroup>
<ScaleTransform ScaleY="0.8" ScaleX="0.8"/>
<SkewTransform/>
<TranslateTransform/>
</TransformGroup>
</Image.RenderTransform>
</Image>
</Grid>
</UserControl>