[Solved... Sort of] Help With Raytrace Procedure Blocks

I have a simple question: What do the Outline, Collider and Visual block modes do in the the look X/Y/Z pos of <entity> procedure blocks? And also, if none of them stop at an entity, how would I do that? (I am trying to make it detect if the player is looking at a living entity and I am using get nearest entity at X, Y, Z in square of size 1 in combination with the look X/Y/Z pos of <entity>)

Thanks in advance!