what i meant is that shadow casting of lights can be turned off. this can be helpful if you want to use it as a fill light which shouldn't cast any shadows. shadow casting of objects can be turned off too. you just have to make such objects passable during the light mapping process.

there doesn't have to be a special uv-set. it is supposed to work automatically with every model but i haven't tested it with very complex ones yet. i hope it will work with other models too and not only with my simple test models.