ok, so agent rating limits the software rating, so your dicepools are Agent 3, software 3, hotsim 2 for a total of 8.
You roll to hit the threshold of the system rating of what you're hacking with an extended test. This is a simple lock, so its device rating 2=system 2.
This will get you a user account which is enough for the door. Every roll you make, they get a detection roll. threshold for detection is your stealth software rating.
The door should be an easy hack, camera not so much.
You'll need a security account on the camera to loop it though, which would make it threshold 6 on an extended test (cumulative -1s in play remember) so it'll take a good 4-5 rolls barring glitches to hit that threshold.
its doable, but the camera might detect your intrusion as it'll need to hit threshold 5 on you as well.