Any question answered...

Spray lacquer is available from any good auto store and can add even more shine to your part or seal it if there are any areas where the resin has been rubbed through all the way to the carbon fibre.
If you choose to spray lacquer your part follow the instructions on the can (including the safety advice) and give your part a number of coats, making each one as light as you can.

It would appear so...
From here
Although, the link recommends multiple coats, which might give you fit issues.