Everything loaded fine in Chrome (8). Took about 5 seconds to load.
My two main suggestions:
First, the page feels too cluttered. The biggest culprit here is the region that includes the sponsor's logos. Find a way to break up the page appropriately.
Second, get a real host and a real domain. Hosting the site on dropbox (while I love dropbox and this is certainly a novel use) is not practical. Judges may or may not wait that long for your site to load, and if they do they will take off quite a few points for that.
You can find hosting that includes a domain for as little as 3 or 4 dollars a month. I personally like
1and1.com., but there are plenty of others. You could even find a free host and pay $10 a year for a domain if you were so inclined.
A real host will expand your opportunities for the site in the future and will drastically reduce load times.