This is a couple ideas I had for STAR but was a little late. Here was one of my ideas:

Part One-Plagueborne crew captures a cargo ship
Part Two-Plagueborne crew searches for an acient warp key.
Part Three-They learn that the warp key has been stored in the armory of the Ship
Part four-They Get to the armory, learn that there are thirty armed veterans guarding the warp key.
Part five-They gain acess to the warp key.
Part six-They have to escape the ship, it is being destroyed by a warpstorm.

Back Story:

Plagueborne-A raiding ship used by the Death Guard Chaos Space Marines to raid Imperial Shipping and harrass the Imperiums supplies.
Space Marine-A geneticlly engineered warrior standing 8 feet tall wielding a mighty .75 calibre weapon firing high explosive mass reactive shells. He also has Power Armor, one of the toughest armor known to existance. He has unflinching loyalty to whoever he serves.
Warp-A relam not part of the material world filled with daemons and monsters only a physcotic lunatic could imagine.
Death Guard-A leigon of space Marines Devouted to the god Nurgle, god of rotting and decay. Makes the already durable marines nearly invincable.

                                                      Effects Guru.