haha okay.
but why a dialog? What is the reason?
(placing my yellow message container in a dialog shouldn’t be so hard though.
Lars,
Thanks for the efforts… it looks great and I will try it out!!!
Depth, it helps with the focus and readability for the user (note that in this quick and dirty example it has not the best layout for content)
Also, there is a problem WITH XOJO. It has no concistency across platforms, Do your example has a semitransparent background in Mac like the gif I posted? In windows does not, the user has noting to focus on.
This way, the “hole” points to the control and making the text being “another thing” outside the window, it is easier for the end user to grasp the explanation being not part of the window and that it is about the control in the rectangle.
PD: Also remember that XOJO has a buggy drawing on windows, doing like in your example (overlaped controls) you get some weird flicker.
PD2: It could be a yellow message, just add a little depth ilution (borders, shadows, etc)
Dang, as slick as this is on the Mac (thank you, Lars!), the lack of transparency on Windows is a real bummer. I’m glad I didn’t get too emotionally invested in it before you pointed that out. I suppose I could just use solid window background color, but it loses a lot. 
I didn’t know, that Xojo isn’t able to draw semi transparent on Windows.
I didn’t tested it on Windows but I thought the crossplattform promise of Xojo would do that.
Anyway, I already have an Idea to achieve this, so I‘ll get into this later this day.
I never had to develop a programm for Windows in Xojo. But dang, the Windows implementation of Xojo is so frustrating.
I have no clue how to make semi-transparent controls here. The “transparent” options doesn’t work, colors with alpha-values doesn’t apply, even semi transparent images (png or svg) doesn’t work.
How do you guys make modern Interfaces with it? Seems impossible.
Okay, back to topic:
has someone an Idea how to build semi-transparent backgrounds to bring this library also in a windows-usable-state?
With other tools that cannot be discused here 
As far as I know, it is not possible due to Xojo limitations. A whole windows can be set to semi-transparent state with Declares, but also the content becomes transparent, that is why you need a window to be the background and another to display the help content