You can't add new colors to a palette, you can only replace existing ones.
Turalyon is referring to this:
Code:
;STATUE OF LIBERTY
[CANEWY04]
Foundation=3x3
Height=15
NewTheater=yes
DemandLoad=true
Palette=lib
CanBeHidden=false
P.S. Someone should ask XGamer to add this to his art.ini guide.