cant register

hi, my teacher at school dowloaded unity3d for me because i do not have the internet at home. after i installed unity3d on my home PC it said i need to register. i am unable to register at home, but would i be able to do it on a public libary computer? how do i register?

@agoasafsitner is correct. You may need internet connection, the manual activation file, or may need to install it on a LIVECD.