It won't even open – iCircuit Review

I'm supposed to be able to use this for school, and can't all. It's downloaded, and everyone was given their codes and they use Canute theirs. I can't even open mine because all it does is display waiting beneath the app icon as if it were finishing a download. There's nothing to download because it was already done. I don't want to delete the app and then risk having to pay for it to download it again. Thank you for causing me to not be able to finish my labs and such.
Review by Tishgacham on iCircuit.