LEGO STAR WARS: The Force Awakens

The walkthrough writers give a good description on completing the level:

After the opening, head right and to the back of this area until you spot a crane and a bunch of floating, alternating blue symbols in the air. This means that certain characters (including Poe) can press to scan the area with binoculars. Move the focus to the end of the crane (note that the central reticule gets smaller when you're 'warm') until you get another button prompt. A grapple point will be revealed. Pull on it to release a multi-build. Build right to create a jump pad for BB-8. Once BB-8 is up on the crane, as Poe smash the jump pad and build left. Spin the crane to allow BB-8 to reach one of his lock puzzles. Once unlocked, head into the hut, smash the centre bricks and rebuild them into a BB-8 switch. Once BB-8 is latched on you'll need to keep the dial in the yellow area with for a few seconds. One weapon cache down, one to go. Head to the building right of the crane. Smash the glowing object in the foreground and rebuild into another BB-8 switch. Again keep the dial in the centre. Smash the glowing objects inside the building to build a droid, who also happens to be weapon cache 2. Time for a cutscene.
Deal with the Stormtroopers and then pull on the grapple point at the base of the tower, right of the burning transport. Build a cannon from the debris and use BB-8 to fire it. Next is a Blaster Battle (and another opportunity to earn several of the extra achievements mentioned in the Prologue). Take out 15 Stormtroopers to move up. Move right to another binocular scan point and scan the side of the hovering transport. Shoot the green lights several times to destroy the ship. Then head left and take out the explosive crate to the left of the protected cannon to destroy it. After the battle, head left and pull on the object next to the tower. Multi-build left and get BB-8 on the device you've made to pull over the tower, dousing the flames. Head through and pull the grapple on top of the transport. Build and solve a BB-8 lock puzzle to resume. Shoot the glowing objects right of the Flametrooper and guards in the foreground. Build left to distract them long enough to take their shield down, and then destroy them. Head forward to the water pump and multi-build left. Jump on the pump button to pump water into the machine in the background. Smash your multi-build and rebuild forward. Have BB-8 bring the water from the left to the right. Break the build again and rebuild right. Pull and hold the BB-8 switch to douse more flames. Run towards the Stormtroopers to finish.

Here is a video walkthrough:
Credit to HappyThumbsGaming.