The news item Nikodemus refers to would be in line with the quote about "when you get back, you get your stuff back" that once was on the site, which implies that it's not with you in the DR. It obviously is quite easy to imagine that something like this would very likely be not yet implemented, and indeed the easy way would have been chosen as preliminary solution: teleporting to a different map. Which, obviously, is precisely what is in PS ATM. Therefore it may indeed be the case that only soul travel is planned. However, that contradicts the notion of "a place with cities and people being able to "live" in the DR", and also the idea of wars "DR vs. WOTL", at least in the common notion of a fight and "living".
However, what I have never found any reference to is the point about respawning in a random body. It would re-add all the issues about having a forcedly fully random char creation, and therefore is something that should not be done. It might be possible to RP it that way in special circumstances, but not as general rule IMO.
Also, as usual, a note about "It's fantasy!" seems in order: Yes, PS
is fantasy, and yes, in "fantasy", everything
is possible.
But this is valid only until one decides on a world, on a setting, and after that has been decided, then there is no more "fantasy" allowed than the setting states there is. To put it in a concrete example:
When there is a PnP RPG in which death is final (there are several), then even though these are "fantasy", you'll still not get your GM to accept your "My char just came back from the dead, since it's fantasy, everyone can if they want!" reasoning. Nor will your other players. Unless you reach a group-wide agreement that in your particular instance of that setting, death is not necessarily permanent.
Transducing this to PS, this means that you would have to reach a community-wide (devs and every player included) agreement. The impossibility of that rules out such an option for PS.
Therefore, we can not define things like this in PS. We must try to find out what the devs really intended, and fill in the gaps by the most likely version, the one that has most backing in the settings, not in the implementation, since the latter, as has been uniamously accepted AFAICS, is not adhering to the settings for OOC reasons like pre-alphaness.
@Anfa: the quest is still quite possible in an RP setting that lacks causal DR travel. To RP that, you'll obviously need to find a RP way to enter the DR, and get back out. That can be a powerful necromancer, a priest, or some other, less general way (like finding a scroll, or a dimensional rift, etc.). The trip may also not be permanent. It could be that your travel provider can keep you in the DR for a set time only, like IRL you can remain in space only for a set time. So you don't necessarily have to fully enter to solve that quest, smoothing out the issue of the inventory in that case. (Though I think that this quest and trainer location is, to put it mildly, not wisely chosen for the current development stage, since it obviously creates confusion that takes some extra thinking and background information to get it set right, something that can not be expected of the average player.)
To find a dark way trainer in the DR is also pretty likely. There surely are some in the WOTL as well, but harder to find, obviously, and not implemented yet, too. But it is established that not implementedness doesn't mean that it is meant to be RP'd as such. Do you
really RP that you can't find a merchant that buys animal remains outside the DR? Surely not, so why would it be any different with dark way trainers?
So the conclusion is that you IC-ly train with some dark mage in the WOTL, while you OOC-ly train in the DR. This is just like the mines... does anyone truly RP that they simply walk into
the temple of a god that really exists, completely ignoring the priests (running right past them), into the inner sanctum(!), jump into the sacrificial well in order to do something as mundane as
mining? Surely not. The real thing would be to simply use a ladder to access the blocked entrance. But there are no movable ladders in PS, so people go that route... RP? Part of the settings? No. Mere lack of implementation. The
spirit of that arrangement is "there is a ceremonial well in the temple, where sacrifices are made to Laanx. This well is, possibly by chance (erosion / cave-ins), connected to an ancient dungeon that is neither well explored nor safe to enter (though the bridge means that there either once was an exploration going on there, but the state it's in hints that that has been long ago, or it is now used as a deadly maze for living sacrifices to die in.). There also is a place where ores can be mined, but the access to this was the warehouse which likely has been sealed (by a wall for lack of working doors (implementation issue again)) by the one who owns the mines, so getting in isn't easy (and would represent trespassing, if not theft, if it came to a trial, if this mine was the only one in Yliakum (again, by definition of the setting, not the implementation))."
An entrance to a mine from the inner sanctum of a temple clearly is suitable only for a god of mining, which Laanx is not.
I find that many quests are hard to make part of RP, simply because they are more or less unique. Take the familiar quest, for example. It is highly unlikely that Levrus would ever need that done twice. So two people can't really RP to have been on that quest, so they can't RP to be on that quest. Same with Brintec fur research. They are SPG-like quests, and as such not suited for IC use in a MMORPG. (With Levrus you can claim some special weirdness of the person, but not with Brintec).
All of this does not mean that PS is like RL. I don't see where I might have raised that view which Syilph seems to have noted. In RL, there is no DR from where people come back, even irregularly. So the water, to a certain degree, already flows upwards in PS.
But it does so to the extent the settings states only, not to the extent the implementation or even less to the extent player laziness states, not even close. Also, even though technically it might run upwards, a well-thought out setting must provide some pseudo-natural laws that not only state the fact, but also the reason and the effect. Like in this case "where does the water come from if it vanishes into the sky"? PS-wise: why is it that even though noone dies, yet people still get born, that there still is space left in Yliakum? So there is a limit to the degree of freedom even in an unformed fantasy setting. Since we have the twin facts that there is a DR, out of which people can get back to the WOTL, yet there is no overpopulation in Yliakum even after centuries of continued birth, there must be quite a high loss in the WOTL->DR->WOTL transmission. A loss that, even if not 100% as IRL, will need to be carefully considered by the living. Would you purchase a car that explodes with a 99% chance? So obviously even with the theoretical chance of getting back from death, Yliaki would not risk dying without real need, so things would not change much compared to RL.
It also quite obviously brings up the question of aging. If noone ever really dies, then noone really ages, as aging is simply a degrading process of the body, just like is being burned to death. If you are being burned by a spell-effect like meteor, or forcibly aged by another spell effect, then that would in no way differ from the real thing. If you then come back in one case, then you also come back in the other, or that other case does simply not exist (and indeed we don't have life expectancies in the settings, though there are the vague notions about middle-agedness in NPC descriptions.).
Thus things aren't as free as the lack of expliciteness in the settings might suggest, as many things just follow from RL, for the simple lack of other options. These in turn force certain other conclusions that eventually narrow down the truly possible explanations.
@Nikodemus: the settings references a "soul" where it says that "once the soul has departed the body, it's just rubbish" (burial wells). So there is the notion of "soul".
@Kerol: (Thanks!

) Using the DR (as well as any other place in PS) as different place than default, clearly does not constitute a breach of the settings, but requires the concrete introduction and likely /grouping you mentioned. But even the "high loss" view does allow for meaningful RP of the DR without transposing it elsewhere.
Anyway, as the actual DR hasn't been defined well by the settings team yet, as well as things surrounding it, the most important thing is to prevent death from losing it's bite in RP. It does not matter what PLs do, not even those who try to make their PL look like RP, nor the abusers that use death teleport, nor bugs. The DR occurs in RP seldomly enough to be able to make do without proper background there, and use an individual interpretation akin to the one Kerol and others have presented in case of need, after agreeing on that with the group of RPers the RP takes place in, without affecting the remaining community (by not definging it as "the DR"), or a different approach.
That uncertanity can, as stated earlier, be made IC, as with this view, chars know even less than we do, for the most part.