>>Hi,
>>
>>If you look at the attached image, you may notice that the label controls have a darker shade gray background.
>>What cause this? If not for this dark background, the label would look on the form "cleaner"
>
> .backstyle=0

Of course there is the potential problem with transparent background with some controls due to "side effects" of antialiasing -- subsequent repaints of screen would cause the text to look "smudgy," and in low bit-depth colour (16 color mode, and sometimes 256 color mode -- though those modes are probably not likely nowadays) modes you could start getting "speckles" of various colours from dithering.