Hello there.
I created a gimp color palette based on Imperialshadows color chart. The palette can be used in The Gimp and Inkscape. The color names are based on official Lego names.
Just place it in the corresponding palette folder.
In Linux it should be
for Gimp: $home/.gimp-2.2/palettes/
for Inkscape: $home/.inkscape/palettes/
In Windows it should be
C:\Documents and Settings\$USER\.gimp-2.2\palettes\
C:\Documents and Settings\$USER\.inkscape\palettes\