I notice the same thing, whatever the high and low 3D are they take over, although 3d high appears to be the lower and darker color and 3D low appears to be the 3D higher lighter color.
Yes, or swap3d=true will do too. Anything that isn't zero or null.
If I use border red and 3d grays, is the border red supposed to disappear?
Probably, if you think this is wrong, let me know and I'll have a re-think about it. We are hopefully at that point with the menu where we can make these tweaks easily enough.
I don't know what is normally expected of 3D, I have white on white so the 3D doesn't do much, therefore I thought that border red would create a different effect as you say it takes on surrounding color.
More important is menualign center 100% so that it stretches the full width and stays with the browser width. I'm adding screenposition to compensate but that doesn't stay with the browser.