right now I'm working on the new design for our .net software and I'm completely stuck at the login form. What I need is a form that is a hexagon with a transparent blurred border. The hexagon form isn't the problem (I achieved this via the transparenceKey property), where I'm stuck is the blurred transparent border.
If you have an idea how to achieve this (best would be on Windows 7, 8 and 10, but right now I take anything) I would be glad if you could point me in the right direction. So far I tried the opacity property and the PerPixelAlphaForm from here but couldn't get good results.
I uploaded two pictures to this question: the first shows the conecept of our designer, so this is how it SHOULD look like. The second image shows my work so far (the labels for username and password are missing in that picture, but you get the idea).
Thanks in advance for any help you guys can give me.

