Honestly, I doubt that time travel is possible in Felarya. There are already dimensional mechanisms in place to allow physically impossible beings to exist, to mimic the functions of a normal world, to ensure that Felarya only links up to specific kinds of worlds (worlds that are habitable to humanoid creatures, or already are) etc. I doubt that whatever force keeps the balance would let something like time travel happen..given that time paradoxes have a habit of completely wiping things out.
I imagine Felarya runs in a linear path through time, just like the rest of the universe. If you allow time travel, a whole new can of worms is opened, and destruction is ensured.
As for the aging on Felarya. A person in Felarya will age normally, up to a certain point. Once they reach the age where any futher aging begins to degrade their bodies (usually mid to late twenties in humans), they stop aging. No one born in Felarya ever aged past their physical prime. People who appear older would have come to Felarya at that age. The healing factor would kick in immediately, preventing further aging.
From what has been discussed, the healing factor's main fuction is to prevent physical degredation caused by aging. Once the body begins to decay, even a little, it kicks in and stops aging, rendering the person "immortal" in a sense. It also seems to super-charge the person's immune system, so that they are immune to most diseases, or suffer very little effect. The only way to get "sick" on Felarya, it seems, is from curses or parasites. The healing factor also super-charges the body's natural healing ability. It isn't instant, but it works a lot faster. Injuries that would take months to heal (broken bones, for example), might heal in a couple weeks.
You can still die though, of course. Mortal wounds are entirely possible, and continuous, rapid damage from things like fire, acid, etc are just as lethal as they are anywhere else. Basically, any non-lethal wound is ALWAYS non-lethal. It will eventually heal, and there seems to be little to no chance of an infection, due to the increases to the immune system.
....kinda got off-topic there ^_^; , but I figured I'd post that, since discussion of the healing factor was coming up.
Either way, I doubt the possibility of time travel, for practical reasons, and because that really isn't a path that needs to be opened, in my opinion anyway. It would just cause more confusion and harm than anything else (like time travel nearly always does =P).
But that's just my two cents on it.
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