This is a problem that occasionally occurs if you are using Windows 7 and Chrome.
For some reason, sometimes Chrome assumes the computer is a touch-screen device, rather than a normal computer.
FROG loads up its version for the iPad, which you can't control properly with a mouse.
SOLUTION 1: Try using Safari or Firefox!
SOLUTION 2 (For Chrome):
This is a bit involved, and involves changing one of the behind-the-scenes settings in Chrome.
Click on the following link to download a .pdf document which will lead you through what to do.