I thought I posted this last night but I guess not...
1. Does the Update Phase happen kick in on the last turn? Do I still upgrade Novice Workers and pay wages to Active Workers and Retired Workers and all that good stuff?
Why not to have the update phase during the last turn? You have to finish the game turn before final scoring.
2. Can I use different Worker Camps in the same turn? That is, can I have multiple workers on the first spot of the novice track?
I'm not sure about that one, so I won't lead you astray.
3. For the Temple of Venus, if the fifth positive position on my track has 9 printed on my player board, do I score 5 for my position or do I score 9 (which is the number that is printed on my player board)?
IMO, that's 9 FPs (the number printed on your board).