On a slightly different note I'm really tired of all the "expletive deleted" paranoid security crap at these schools, not so much talking about the computer, but things like THERE ARE GUARDS IN THE SCHOOL!! I went back to my old high school not too long ago to visit my old teachers and such during breaks (other graduates used to walk freely like this through the rooms even sit in on classes) As soon as Iwent through the first main doors 2 guards stopped me and told me I had to leave the building, the only person I could talk to was some the secretary at the office, who I had to argue with for 30 minutes just to get the principal to speak with me. (keep in mind ALL the staff knows me and had for 4+ years, save for the bumbling guards) The principal told me the biggest bunch of crap I've ever heard, about how me being there comprimises security and yada blah, I was even allowed to speak with the students. It's just pretty much retarded having graduated for less than 5 months and being escorted off the campus... These people need to quit acting like elementary schools are the grandiose epic idol monument of our time that must be kept clean from these evil 18+ people that didn't decide to pretend they never attended these schools or built relationships with the teachers they knew for 12 or so years. Whether you were normal, the class goth, the star jock, or the prom queen. Not to mention for all the "OMG PROTECT THE SCHOOL AND ITS STUDENTS FROM THESE INFIDELS INTRUDERS" they only give a "expletive deleted" between 8 am and 3 pm, then they could care less if they get shot or blown up or even worse, *shudders* talked to or visited.
OK rant over on security stupidity
So as for your problem, they know you're capable of getting around some of their stuff, and that you comprimised the safety of their C: drive..... just accept what you are or aren't allowed to do, APOLOGIZE TO THEM FOR IT! and tell them you'll be sure not to mess around with what you're not supposed to, then they'll be happy, and you can quit worrying.
Decent people are suckers for common decency, if you admit being wrong to do it thats generally going to satisfy them, if it's voluntary.