Try to load them into image control at application startup so they would be cached with transparency attribute.

>Seems that displaying PNG graphics is broken in VFP9 beta
>I've tried to use some nice button pictures with transparency but the trouble is that somtimes the background is not transparent. Not always.
>
>I've tried the same pictures in .NET and the picture is displayed correctly on both forms and buttons, always.
>
>Pitty, because PNG is an excellent format to use for buttons.