Chanukah

I grew up lighting Chanuka candles inside the house. In my community, the uniform practice is to do so outside. I think that is great, but I miss seeing them inside my house. Is it permitted to light a second chanukia indoors (could it be bal tosif)? If permitted, what is the best way to do it?

When to Light the candles on Friday night? Where should I light if I'm staying at someone else's house for Shabbat? Should we light before or after Havdalah?

Last night by error, we lit only 5 candles for the sixth night of Chanukah. What would have been the proper way to handle our goof up?

A guy who came home late and the only one who could wake up was none other than his father.

Who is obliged, and who is exempt from Chanukah candles? Do women, children, Yeshiva students, soldiers and roommates light their own?

If one only read the Al Hanisim that appears in the Shemonah Esray and benching, one would not know much about the miracle of the oil. Perhaps the lighting is a public manifestation of a miracle that is much more difficult to publicly commemorate.