That seems to be warband/map problems. Happens to me sometimes when i try and pick up a dropped weapon, i can't cause i can't "see" it.(you can with some REAL careful looking/character positioning.)
Happens in strat and regular crpg.
It can happen with any weapon. I think a lot of the time what happens is another weapon or shield is on or near the one you want to pick up. If you don't have the skill to pick it up, it just won't show up on your screen as the option to pick it up, and items nearby are hard to see the option to pick it up (if you run around and move the mouse in circles near it sometimes it will briefly show up on your screen).
I find that running back and forth over the item and keeping the mouse still works the best. You should eventually see the option to pick up the item you want, the problem is that you need to move your mouse away from the item (basically like 180 degrees) before it will ever show up again. It's a glitch that I've seen in native, c-rpg , and a couple other mods.
