New Super Mario Bros. Wii 7-Fort QSC

I got the 2nd Star Coin at the top of the first part of the level. There is a gap in the ceiling to the left. In the lower right corner of the gap is an invisible block. I jumped on the block and ran across the ceiling to the right. This will take you to the 2nd part of the level where the 2nd Star Coin is. I got the 3rd Star Coin by blowing up the bricks in front of the Star Coin with a Bob-omb near the top of the level. This took several tries. Underneath the 1st set of double Bob-omb blasters from the top is a ledge protruding out of the wall. I walked into the wall from this ledge and reached the red goal next to a stone gray castle. This creates a vine to 7-6.