Adding syntax coloring to Signature Help for custom language service

Hi all,

I've added signature help to my new language service and now, I'm trying to apply some syntax coloring to it.

I suppose I have to export a SignatureHelpPresenterStyle and override some of the properties?  The property handlers don't seem to get called.  Any clues?

    [Export(typeof(SignatureHelpPresenterStyle))]     [ContentType("code")]    [Name("Signature Help Presenter Style")]     [Order(After="default")]     internal classMySignatureHelpPresenterStyle : SignatureHelpPresenterStyle    {
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