Really old, but some of it is still valid.
Quick note: light maps work based on character positions in the scene, which in turn depends on where you set the character animation center for each of the characters animations (usually somewhere near the feet). The engine checks if a light map is assigned to the scene & then checks the position of the character against the light map & then tints the character based on the color found at the pixel coordinates of where the character is standing.
P.S: this tints the entire character.
P.P.S: it's a good idea to add feathering as shown in the examples on the glenfx tutorial page as it allows the player tint to smoothly change from one tint to another as opposed to instantly snapping between tints.
P.P.P.S: it's actually possible to tint your characters manually using Lua script instead of using light maps, although light maps are definitely much less complicated.