There is a clear warning in the software outlining the need for a battery charger on the vehicle and having the laptop in high performance mode. Your laptop dying quickly is not something that has anything to do with KTuner and you may want to look into a new battery or laptop to remedy that...
As noted above, if the unit is unlocked properly you'll be able to lock it to your vehicle and use it. Have him show you the verification step outlined in the online help for locking/unlocking the unit.
Short of the clutch being the weak point the tunes available are highly reliable. See the CivicX forum for long term reliability feedback. We expect the same here over time.
Knock retard is based on the knock control value. The ECU has windows of detecting noise from the knock sensor and sensitivity settings which depict KC movement.