Got my Hawk 250! Couple questions

[TheDill]

Just built the bike and have a few questions.
1. What are the MOST important pieces to take apart and loctite?
2. The rubber piece below the chain on the frame of the bike, the chain is rubbing against it is this normal?
3. The gasket around the exhaust manifold was like half way out from the engine and the manifold then fell off after first start is this normal?

Any tips/tricks are welcome!