Office 2007 Beta2 Ribbon image transparancy

[NeilL]

I'm not sure if this is the right place to start but sounded close.

I've installed the Office 2007 Beta2 release and I'm working to modify a VBA
application to use the new UI Ribbon. In the "old" days I could retrieve an
image from a resource DLL as IPictureDisp along with a Mask IPictureDisp and
set the Picture and Mask properties for a menu or toolbar button.

In the new Ribbon UI I've set a callback using the getimage XML attribute.
The callback has the following VBA signature

sub GetImage(control as IRibbonControl, ByRef image)

and I'm able to retrieve and pass back an IPictureDisp object in the image
parameter. That all seems to work properly.

My question is how to either make the image that I'm returning transparant
or is there some other way to set a Mask (or some equivalent). What I get
are images displayed for my Ribbon items but they are not transparant.

Thanks and if this is not the right place for the question a pointer would
be helpful.

 

[NeilL]

I'm assuming that since I have not had any response to this post that no one
knows or it is not possible.

I've looked at all of the documentation I can find without any luck at all.