One wiki described warp as follows, "Warp: A corruption of the characters mind and soul, inflicting progressively more dire effects upon them. While the effects of warp can range from annoying to deadly, accumulating enough of it can also grant you access to greater power... at the cost of increasing madness, and attention from dark powers. At least, others may call it madness... but is it truly insanity, when the voices in your head grant useful knowledge, and the monsters that appear before you leave remains behind?

As for ideas as to how to intergrate this, simply by being in the presence of such abyssal beings, can cause some of the effects that are normally applicable to some degree of warp.

In this regard, fighting regular mobs has a chance of causing temporary warp.

Fighting mini bosses a chance of normal/"sticky" warp.

And of course, fighting bosses has a chance of permanent warp.

As for the dimensions added by the mod itself, I feel that gaining some temporary or normal warp every few minutes of actually being in the dimension would be applicable. You are in a maddening dimension after all.

As for which effects, I think that getting sun scorched after leaving the shadowlands would make sense. You were just in a realm of living shadow, and some of it may have stuck to you upon exiting.

Unnatural hunger is an all around good one to get in any dimension. Best to carry some rotten flesh while exploring the areas. (And some mobs in there drop some too, right?)

If the statues occasionally whispered secrets to those in range of the disruptions, it would create a balancing act of how bad do you want these secrets. (Aspects for research) (though gives me a new idea as well.)

I like the idea of the mind spiders as well. Mobs that only you can see, but can still hurt you. Would be interesting if you added an effect like that, but with your mobs. Reminds me of a story that way. Maybe make some mobs that can only be seen with goggles of reveling (and some kind of equivalent by your mod.). And can only be hurt by those who can see them & vice versa.