Answer 1: Simply talk to Canderous enough times, ask him about his past, and so on. The quest should eventually be triggered. And no, I don't recall anything about Canderous' and Juhani's sidequests being related.
Answer 2: I'm not sure what you mean by this question.
Answer 3: To be frank, I don't think it's worth it to take yourself to Manaan in the first place. But since you have to go there eventually, then yes. Bastila is arguably among the three most powerful party members available, so having her escort you around could be mandatory, depending on the difficulty level.
"There is something going on in time and space, and beyond time and space, which, whether we like it or not, spells duty." -Winston Churchill
"For of all sad words of tongue or pen, The saddest are these: 'It might have been!'" -John Whittier
"Apathy is death." -Kreia
Last edited by TKA-001; 04-08-2008 at 06:53 PM.