Thanks for a quick reply.
I've changed the code as follows.
No luck. I still ended up with a regular white background. The sample is here.
BTW: Can an Image format (MagickFormat.Png) has any relationship or effect the result I'm trying to achieve? Maybe the problem is here?
I've changed the code as follows.
var backgroundOfWaterMark = new MagickImage(new MagickColor("#FFFFFF80"), image.Width, 20) { Format = MagickFormat.Png };
BTW: Can an Image format (MagickFormat.Png) has any relationship or effect the result I'm trying to achieve? Maybe the problem is here?