I had a real nice elven bow that all of a sudden wasn't in my pack anymore,also I believe a great x=1 was missing earlier has this happened to anyone else?

Quest items will be removed from your pack as you go from chapter to chapter. There is a great axe that is a quest item in chapter 2. That might be part of your problem.

Some monsters and NPCs have a disarm attack. I don't know what happens to the weapons they disarm from you. I would assume they go into your pack, but they may fall to the ground. I've never actually experienced this.

when monster disarm you, the weapon will fall into the ground, pick it up and then equip it. very annoying when this happen.