When I lay a trap it doesn't seem to activate when an NPC goes over it, Am I doing something wrong? Any advise, thanks

traps only activate when enemies are near, not with friendly characters

Are you trying to kill your NPC's

Sorry, did not mean friendly characters. Various enemies characters seem to just walk past them. I layed down all 5 I had in the pebblecrusher battle and did not see them activate.

You get the animation for setting it even if you fail! Check the text box to see if the trap was set successfully.