Hmm, my alarm did not go on after I installed it.
I'm wondering if I did something wrong, although it was so straightforward, I cannot imagine what that would have been. The place I called also said they needed to do an update, which folks on this site say is entirely unnecessary. They were only going to charge me an hour's labor, though. I'd still hate to bring it in, have them charge me and then not have the alarm work.
As far as disconnecting the battery--didn't you disconnect it when you installed the alarm? Just disconnect the terminal.