It was interesting and pretty good. I expect you'll do well in the competition.
~Scoucher's One Thing~
"They were in a room, a large room, in the middle lay a giant machine that was controlled by the millions of Elves that operated it."
First of all, this is a run-on sentence. Should be, "They were in a room, a large room. In the middle lay..."
Secondly, you might want to write "...machine that was operated by millions of Elves," rather than, "...machine that was controlled by the millions of Elves that operated it." The latter is redundant.