Welcome aboard BearFan! I'll try to answer your questions in order the best I can.
Pork loin is fairly easy. I like to simply apply my favorite rub (lots of good rub recipes out there), then smoke it at a smoker temp of around 230* until the internal temp (IT) of the loin is about 155*. Some people like it a little more rare, but for pork I always shoot for at least 155.
I've never used pellets in the MES chip tray, but I'll bet they'd be fine...if not, chips will certainly work until your AMNPS arrives.
I never put water in the water pan of my MES...usually just covered it with foil for easy clean up. Many members put sand in the water pan to act as a heat sink.
This is still occasionally debated here, but IMO soaking wood chips is a waste of time. They won't begin to smolder and smoke until the water in them evaporates.
The control console is on the top panel in both 1st and 2nd Gen models...On the 2nd Gen MES models its at the front of the top panel, while on the 1st Gen models, it's at the back of the top panel. Also, the 2nd Gen models have an exhaust vent in the left side panel of the cabinet...in the 1st Gens the exhaust vent is in the top. If you've had yours for 2 years, chances are its a 1st Generation.
If its a 1st Gen, it'll have 2 stainless rods/rails across the left bottom of the smoker (just left of the chip tray and heat element array). This is the best spot for your AMNPS. If its a gen 2, I think I've heard those rails are missing. If that's the case, you might browse through the electric smoker forum threads for tips on where other 2nd Gen owners place theirs.
I hope any of this helps...Good luck!
Edited by SeenRed - 1/3/14 at 6:57pm