I dont want to go into too many details so as not to spoiler people but I have been reading the adventure and it seems to me that there are an awful lot of 'people' surviving on this space hulk without their souls getting eaten/tormented for eternity every time it goes into the warp.

It specifically states that one individual has survived alone on the hulk for 'several weeks' and we know from the adventure that the hulk has been in the warp on at least 2 separate occasions in that time! There can't be lots of functioning gellar field pockets all over the place (I'm sure the book would have mentioned that) so is there another explanation for this? Or is it just a plot hole?

Kinda boils down to how you want to wave it away. Genestealers hitch rides on Hulks all the time, and none seem to mutate. Same for Orks. I know there's (flimsy) fluff out there that hand waves GS/Ork resistance to the Warp, but still...

I would say it depends on where this individual(s) was located. If in a functioning ship, or mostly-functioning, then sure, have a Geller Field in operation, and maybe reduce a Librarian's Psy Rating by a point or two as a result of being partially cut off from the Warp.

If you don't find a way to explain the survivor's inexplicable resistance to the Warp, then it's a plot hole you can fly the Hulk through. EDIT- Your Players won't believe a normal schmoe survived all this time in the Warp without protection, and the first time it comes up someone in the team is going to put a bolt in the survivor's brain case.

My 'handwave' explanation would be to say that daemons in the warp are attracted primarily to concentrations of souls. They would certainly swarm groups of people who have been thrust into the warp and greedily devour their souls, but a lone guy hiding in a storage closet- one tiny 'blip' of a soul in the maelstrom of the warp- might escape the daemons' notice...

I'm glad it isn't just me!

I was specifically thinking of *******SPOILERS*********

The second mission option in Chapter III. The rogue psyker and his mutant army would surely attract warpy attention... I suppose I can get behing the death cult assassin managing to hide her tiny warp presence and avoid demons like she presumably does genestealers.

For the Orks I would reckon on them putting Big Teef up like they do on their ships. Their 'gellar fields' don't need power just waaagh.

Also while I'm at it I'm not sure about the transition from chapter II to III. The gellar field fails but everyone miraculously survives... I think I would probably change that.

What I'm wondering about is the ecosystem and where it gets its atmosphere from.

What I'm wondering about is the ecosystem and where it gets its atmosphere from.

More 'hand-waving': The 'life-sustainer' systems on voidships probably have their own back-up generators, and continue to function even after the vessel they are on has been smashed into a Space Hulk. If the outer layer of the Hulk is compressed/compacted enough, it might be close enough to airtight (plenty of holes, but small enough that the density of air creates a 'bottleneck' effect that slows down the leakage) that the numerous life-sustainers scattered throughout the Hulk produce air faster than it can bleed out into space. Or something like that... (all this 'hand-waving' is giving me carpal tunnel syndrome...)

When I played the space hulk based DH adventure from Purge the Unclean it had lots of bits where there was no atmosphere. I think it is more a case of some areas have air but lots don't. Certainly when I run the adventure it will be something the players have to consider each time the open a door!