I think we'll eventually see Locke's map show up in an interesting place. Possibly a hatch that the Others are inhabiting.
If Candle/Wickmund had both his arms, that means that the tape predates the Swan film. The Swan film was made post-"incident". My guess is Candle's loss of his limb is directly related to the incident, assuming that such a thing even exists. If it's all pretend, then either he hasn't really lost his arm and it was under his lab coat, or it's related to the "sickness" (Danielle said Montand lost his arm when the sickness happened).
I'm assuming the two names means Candle is really an actor and neither name is real.
What I think is that everyone who works on each of the hatches have no idea what is going on in the other ones. The Pearl observes the others while the observers believe there is one big psych experament. When in reality it is not one.
There's a possibility there are lots of "candle" men because of cloning, although right now I think that everyone who gets an orientation film or tape is being told something slightly different and are all the subjects of Dharma/Hanso experimentation.