Hi Denis!
I see two ways of doing so.
1) Make the picture semi-transparent by erasing every odd pixel. This way the picture will look like a chess-board.
2) Use pictures with alpha-blending. Alpha-blending means that you can specify transparency level for every pixel. AFAIK this is only supported by VFP 8, only for PNG graphics and only in image control.
/A new technology turns into completely outdated stuff before you have a time to read "Getting Started..." section.
/If there are some "system programmers" then others are unsystematic.