They are mapped to I and Numpad 0 (shown as the End key in the menu) but they do absolutely nothing. I can even see what appears to be an inventory window in the lower right corner, mirroring where the automap is, so is it a bug or do I need certain items for it to work right?

is the Numlock key on?

Just wondering because that's what happened when I mapped things to 1 and 3, I had numlock off

Numlock is off. That is why my numpad key is shown is "End" instead of "Numpad 1". Thank you. What about the Item key? Are there specific items I need for pressing that to work?

If I remember correctly, you will know when you have a usable item because it shows as an icon at the bottom of your HUD. You then just press Q (or your assigned key) to pull out that item. Trip mines are one of the usable items (5 uses); they look like a pair of high-tech, oval binoculars/goggles with an antenna. Passive items should show up as icons on the left hand side of your HUD, so I guess that's how we are supposed to make that distinction.