Hello all,
I'm using Rise of the Primes red theme and wanted to remove this little black stripe over the taskbar:

With PS this wasn't any problem but after that, my taskbar looked like that:

(next to the start orb you can see that the taskbar does'nt look like it should...)
So I changed the taskbar to that:

(I made the taskbar 1px higher that the black stripe over it isn't visible and changed the color of the little black part to grey)

I think it looks better now but anyway I want to know why this happens to the taskbar if I make the highest part transparent.
As well it would be nice if anybody could tell me how I can change the height of the taskbar.

I know, many people will call me crazy because I want to remove a thing which you can't really see, but the main problem isn't the black stripe. I just want to know why this happens...
I hope you understand my problem