whoa - now those are good points. I didn't understand about hitting the ceiling! Of course you're correct! Now the research would have to be how fast the bolt leaves the crossbow. It is then a simple matter of maths to determine how far it can travel before hitting the ground - therefore having a chance to pass thru the open legs of most creatures! For the short
goblin and Orc, you can give more range, because the bolt can fire upwards at the same rate as a taller creature, yet drop down further and still hit their lower-to-the-ground chest.
This is such a good question that I will put it to my very experienced DM later today! (HEY It's SATURDAY!! WOOHOO!!!)
As for the corridor search, our DM has already made a vision limit rule - the barb, despite being taller, has a vision range of 7 squares, 6 with wearing a helmet. While my necromantic, dark adjusted vision is 10. This is how far one can
look for a trap, but it is a dice roll. snake eyes - you happen to be standing on a trap and it fires, regardless of whether it is on the DM map or not! Double sixes and you
know for certain there are no traps -
or you are
sure that that quivering section of wall or ground or ceiling is most definitely a badly concealed trap! Everything in between is a % of what you roll. ("
You find nothing." "You think maybe the ceiling might have something, but you can't see anything else." "You're not sure of what you see.") And to disarm, you have to be right next to it, of course. Our crew likes to blast ahead without even checking anyway. The Samurai wound up using a couple health potions from not checking, or rolling badly when he did:

And being a Samurai, he was played that way - bravely barging ahead without fear!
Different races have different vision ranges. The elf, of course, can see super far, and has +2 detect roll.
Once we get into some outdoor adventures, the necromancer's LOS is going to drop right the hell down - he
hates the sunlight!
So I'm quite glad you posted, jester! Now I fully understand your position on those topics, and they sure have merit!
See what happens all you silent readers out there when you
post?!?
MUCH MORE MATERIAL TO READ!!!
wooohooo!