I believe the built in lightmap system should do the trick. The lightmap is essentially an image (1 per scene) that you add color tones into. You assign each scenes lightmap into the properties section of each scene, which the game engine then uses to calculate the tint of the character as their position changes throughout the scene.
Quick note: you can downscale the final lightmap image to 25% or maybe even less of the actual scene size for better optimization as the engine automatically scales it up when the game is running.
Have you checked out the downloads section of the website? I'm pretty sure Fantasy Quest or one of the other available demo games will have some examples of lightmaps being used in them.
P.S: lightmaps aren't as sophisticated as normal maps, as normal maps can generate both light & shadow tints on a character, whereas lightmaps just tint the whole character a specific color. I'm not sure if @SimonS has implemented support for normal maps into the engine yet though.
P.P.S: you actually have to create the lighting lower down to compensate for the fact that it's the characters position that determines which tint from the lightmap it will use - the characters position is the character animation center you specify for each of your characters animations & is usually somewhere near the feet of your character.