Holding shift only applies to VSB and not reshacking.
To the OP: What image editor are you using to create the bitmap?
I'm using Photoshop CS3. Perhaps I'm going about it the wrong way.
What I did was extract user pic .bmp from explorer.exe, opened it in Photoshop, pasted a .png picture over it , deleted the original picture, made a black backround and saved it.
Perhaps this is the wrong way to go about this?