What's the story with point lights and lighting channels?

So it seems with a point light if I uncheck “cast shadows” , then I get good light around it , but it shows quite a bit on the walls , like its reflecting off the walls and ceilings. But if I check " cast shadows" , it does not reflect on walls or ceilings anymore , but then I get no light, is there something i’m missing? Also , if I am say , underground in a room and I put all the walls and ceilings on channel 2 , as well as the lights. , which is all good , but still if sun rises and sets outside , my player character is showing the light on him as it rises and sets , but I cant change the light channel on my character. I mean the option is there on his mesh , but I can’t have him on channel 2 in the room , since then when I go outside , the sunlight would not show on him.