Skin is possible to download and change the lookWhen you have downloaded a new skin copy it to
C:\Program Files (x86)\Image-Line\FL Studio 11\Artwork\Skins
My skins is this.
I have it on another drive. So i copy this to C:\Program Files (x86)\Image-Line\FL Studio 11\Artwork\Skins
And again if i had a place to upload all this skins , i would do. But as i do not have that, then i am sorry to say you have to find it by yourself.
After i copy
Now i can change the look in here: