If you climb up a ladder while having your torch drawn and lit, when you get off the ladder at the top, the light will still be shining through from the bottom.
This happens when the torch is being put back into the character as he/she goes to attach to the ladder. the light origin is still registering where the player WAS instead of taking into account that the torch has been put away.
when you reach the top of the ladder, the torch is no longer in and light is shining through the floor.
pressing 0 to bring out the torch again (or whichever button torch is assigned to) clears the light from the ground.
the whole issue is due to the torch not turning off when being put away while lit {F28362} {F28363} {F28364} {F28365} {F28366}