Binding Image.Source to property doesn't appear, in designer - xaml

Question

I want to bind the Source of an Image (in WinRT XAML) to the ImageSource property of a view model called ServiceEnvoy, which points to an image in my project's /Assets directory. Here is the view model:
public class ServiceEnvoy
{
public ServiceEnvoy(string name, ImageSource source)
{
this.Name = name;
this.ImageSource = source;
}
public string Name { get; private set; }
public ImageSource ImageSource { get; private set; }
}
Here is the XAML of the ListView I want to expose the view model:
<ListView ItemsSource="{Binding Services}"
...>
<ListView.ItemTemplate>
<DataTemplate>
<Button>
<Button.Content>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Name}"/> <!--Works fine-->
<Image Source="{Binding ImageSource}"/> <!--Does not-->
</StackPanel>
</Button.Content>
</Button>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
There's another complication, however: the view model is deserialized from JSON to be loaded onto the main page.
Here is the JSON I have so far:
{
"Services": [
{
"Name": "OneDrive",
"Image": "onedrive.png"
}
]
}
A ServiceEnvoyExtractor class (found here on Pastebin) extracts the view model by appending "ms-appx:///Assets/" to "Image" and creating a Uri/BitmapImage out of that. I'm not sure if that was the problem, but I tried changing the JSON to "Image": "/Assets/onedrive.png" or "ms-appx:///Assets/onedrive.png" and rebuilding, but the designer still did not display the image. However, it works fine when I run it on my phone.
My d:DataContext is: d:DataContext="{Binding Source={d:DesignData Source=/Data/ServiceRecords.json, Type=data:DesignableServiceEnvoyCollection}}"

Answer 1

Well, that was rather simple.
After a few hours of frustrating myself with the type of the ImageSource and renaming it and testing other controls with it and fiddling around with the JSON, I realized that while its key was "Image", I was binding to "ImageSource".
That, and changing its directory to "Assets/onedrive.png" fixed the problem.
EDIT: The XAML also seemed to throw an error about how ImageSource properties could not be serialized; changing the property to type string fixed the problem.