I can answer this! Well, almost. I don't know about using AutoHotkey, but it would rather unusual if it didn't work. Deck don't do anything funky with scancodes.
Changing from USB to PS/2, or viceversa, requires you to change the cable around (Deck does this, the cable has USB at one end, and the other is PS/2. Handy that.) and add or desolder a very well marked resistor. So, I guess that the answer is yes, you do get a cable for both USB and PS/2. Personally, I think you should just buy two Decks, one in USB and another in PS/2. Fixes that issue.
The only thing my Deck came with was an extra Skull n' Crossbones keycap for the escape key. I made a puller out of two large paper clips.
The keycaps do show their seams, which I'm guessing is a manufacturing problem at Signature Plastics, the folks who make Deck's keycaps. I took a 5-second exposure picture which revealed mine has 65 keys that are showing seams. But I'm really not bothered enough (some are very minor) to do anything about it. If yours has this problem, it looks like Deck will send out replacement keys no problem.
There's a lot more info from people who have bought a Deck recently over at GeekHack.org, including myself:
http://geekhack.org/showthread.php?t=14989