I have an Excel 2003 add-in that I am trying to make compatible with Excel
2007. When the *.xla file is loaded on the Add-Ins Tab in 2007, the custom
toolbar button images are automatically and appropriately displayed with the
buttons picking up the background of the toolbar's color. However, when I
try to load the Add-in on it's own custom Tab, and bring the button images in
from the embedded files in the XML package, some of the image backgrounds
are no longer transparent and are picking up the background color of the
toolbar that the image was on when I copied and edited it in a graphics
software app (which doesn't correspond to the color theme in 2007 so it's
pretty ugly). I was really kind of surprised that 2007 handled my add-in
button images appropriately (especially since my experience with Beta2 didn't
suggest this would occur).

However, now that I see that 2007 has some way to deal with this, I am
wondering if there is some way I can access this capability and have it apply
to the images I store in the XML file?

I appreciate any insights.