Okay, a week later and I am finally getting a handle on this. First off, let's deal with what has happened, there was no crashing of the Derma's system, partially because Snow was acting a little too quickly and partially because she didn't have the Admin account necessary to crash it.
What did happen is that the Spider blocked her attempt to start an alarm, and has found her in the system and is attacking her. In the meat world security is alerted and is beginning to act defensively, but Snow and the Spider will get in a round of actions before anyone else engages.