First and foremost, there is no such thing as "maintenance-free" decking.
Even composite decking requires some degree of upkeep - it's 50% wood. Check with the manufacturer regarding the specific care for your product.

Composite decking needs to have holes pre-drilled for the deck screws.

Special screws are needed for composite decking to reduce "mushrooming." An excellent screw for composite decking is manufactured by GRK Fasteners. Click Here for more information on GRK Composite Decking Screws. You can purchase GRK products here.

Composite decking must be spaced according to the manufacture's recommendation. Typically 1/8 to 1/4 of an inch. You may also consider using a few deck spacer tools.