black background in slideshow

[vlad2006]

Hi!
I have MovieFactory 5. SlideShow work great, but if have pictures with some size that not cover entire spaces, then in visible the background that is black. Is posibil to change this color? In UVS is possibil via File->Prefeences, but in DMF i dont see any option.
Someone, sugest to resize the photo, but if i have many can be painfull.
I want to change black color for background, even via ini files or registry value.