Modify default derma skin

Hi. I’m trying to make my own GUI skin. I copied the content of (garrysmod/lua/skins/default.lua) into a new file called “myskin” in (garrysmod/lua/skins/myskin.lua). I tried to load it in order to see if it works but the following error shows up:


] lua_openscript skins/myskin.lua
] 
Running script skins/myskin.lua...
[ERROR] lua/skins/myskin.lua:88: attempt to index global 'GWEN' (a nil value)
  1. unknown - lua/skins/myskin.lua:88

This is in line 88 (I didn’t even touch it, so isn’t it supposed to work?):


SKIN.tex.Selection		 			= GWEN.CreateTextureBorder( 384, 32, 31, 31, 4, 4, 4, 4 );

Also the new Gmod wiki hasn’t documented anything about this topic yet, so I hope you can help me. ^^

-snip-

The global table GWEN isn’t defined.