Will it hurt my Macbook Air to be plugged into a "Uni Pak II" which is a dimming power source?
In general, it isn't a good idea to put a power adapter on a light dimmer as the circuitry could malfunction if the voltage is too low.

That being said, I believe the 45W adapter for the MacBook Air will survive- it just won't charge if the dimmer reduces the voltage below 100 volts. The AC is converted into DC and then applied to a voltage regulator circuit which typically shuts down when it isn't getting enough.