Put it in your micro-wave for 15-30 seconds. If that doesn't work call Tower in the morning and tell them you want more. Don't use a drill on the prop. They sell metric and SAE prop reamers that have steps in them to enlarge the holes to the right size. You use them by hand. Reamers follow the existing hole in the prop so the hole will be nice and perpendicular to the face of the prop if you're careful.

http://www3.towerhobbies.com/cgi-bin...&I=LXEGH7&P=ML