Dreamland and Blueprints

I'm near the end of the game but I've gotten stuck on one of the blueprint puzzles. The game tells me that I've got to put the missing piece into my athlete's gate blueprint. Problem is: it's already in! I can't click on the globe anymore, since I've already done all the plans.

Have I missed a step?

Is it this game?

I'm not sure what's going on, Mary; I hope someone who has played the game can assist you with this. I looked over the Big Fish forum for Dreamland and didn't come up with anything useful, unfortunately.

Yes, Ana, that's the game. I've looked at several walkthroughs quickly and couldn't find anything, but the fact that I don't have an "empty" space in which to put a piece looks like I'm at a dead end.