I gather from this rant of terror that you are playing CSB?

. Oh we are in the CSB forum...that would make sense...
Yes CSB is very evil...even when you know the layout etc. You wil get lost a lot. You will get beaten up by monsters a lot. And as you are probably finding, you will die a lot. There IS a structure to this dungeon, but it's nothing like the linearity of DM. If you want, I or someone else can give you a hint as to what your general aim is atm. But we don't want to spoil anything for you.
Death Knight armour, like knight armour in DM, is cursed...I think this means it lowers the hidden luck statistic of your characters or something. It's bad anyway.
If your characters are overweight, try losing anything you don't think you will need, or creating a storage pile at a central location like the Junction of the Ways. If you find yourself trapped somewhere I suggest just loading up a past save and either going a different way or taking the same path but doing it differently. You will want to save a lot, I think, but don't do so in an area where you think you might die

. I appreciate that this is practically the whole dungeon but...well some areas are less fatal than others

.
And if you can get to the bottom level of the dungeon you will find a nice food supply - it's only a few food items and you must umm...achieve something in order to get them...but if you are starving it is a good idea

. You need to do it anyway, regardless of whether or not you need the food.