Today i noticed a minor bug going on with orc corpses. It does only affect regular orcs.
The thing is, their first corpse stage weighs nothing, and the one that appears when you skin them doesn't either. You can still pick them up and do whatever with them, but they weigh 0 oz. The items that are inside the corpse are counted tho. Other stages do have their weigh as it has to be.
Also, after a certain time, corpses that were at first stage acquire some weigh although they look the same as the first stage (I guess it is normal that there are 2 stages with the same look).