2. Sorry i do not know any plugin to help you do it.
3. That is our document for new feature. That feature will come with theme version 2.0.1.
4. Our theme set price by adult in Tour and Activity service. That is the default theme function.
5. Each price has a separate display and is added to the final price.
6. You can set minium and maxium people in tour at Information tab when you create tour.
7. Yes our theme support deposit payment. You can select that option in Tour Price tab.