Custom UI Effects

I was really happy to see the inclusion of effects like drop-shadow in the UI toolset, since the editor labels them as Scripts is there any documentation on writing custom UI effects or is there any way to view the scripts for the effects currently available?

Not super important, just hoping for as much customization as possible.

Really glad to finally get to play around with the UI, great work!

 

http://www.jetbrains.com/decompiler/

this can sometimes show some parts...