Bug is probably too strong a word for these issues, but I need to call them something.
1) easy_disarm option - from the guide:
this works for known traps in the open, known traps on doors, probably known traps on walls (I don't have any handy to test), but it does not work for known traps under items. if a trap is discovered but under an item, it can be viewed by examination or disarmed with D which only works on known traps, but moving into the trap always just sets it off."Automatically disarm traps" makes your character try to disarm a trap just by stepping onto it.
2) stairways are hidden by traps
this one's pretty simple. a trap on a > or < always displays as a ^ which can make it pretty frustrating to find the stairs. I don't know if that is by design - it may be since I don't really know how else to show it - I suppose by changing the color like trapped doors might work.
I think it's always been this way - we've all just lived with it - but maybe it'd be easy to fix. For someone who knows their way around the code that is
-Pepe