Button.SetBitmapMarigns not working when button is expanded

[Matt Kimberling]

I recently added a bitmap to a button in my Windows app. It appears but it's positioned at the far left edge.  I'd like it to be positioned next to the label.  I've found that SetBitmapMargins doesn't have any effect when the button was added to a sizer with Expand().Proportion(1).  I modified the attached Buttons.py demo and it shows the same behavior.  Is there a work around for this?

Thanks,

 Matt