Hint: mission 7 is actually possible without running to the top of the map! get the crystals first, then use them to build some reactors above and below the ship. put some shields on top of the exit points, then aim 2 repulsers at each. place ~10 mortars, then you're ready!
I really like how the devs have tied LoTS and DotD together. It gives both of them a deeper storyline, and it's fun to try to find all of the connections.
 "Infectonator 2"){kind=icon}
 "Creeper World: User Space"){kind=icon}
 "Enigmata: Stellar War"){kind=icon}
 "Decision 2"){kind=icon}
 "Knightmare Tower"){kind=icon}
 "Bloons TD 5"){kind=icon}
 "Creeper World 2: Academy"){kind=icon}
 "3D Logic 2: Stronghold of Sage"){kind=icon}
 "Trollface Launch"){kind=icon}
 "Legacy of a Thousand Suns"){kind=icon}
 "3 Slices 2"){kind=icon}
 "Bouncing red head"){kind=icon}
 "Reactance 2"){kind=icon}