[Blood Raven]

When you add a license onto your weapon it should be below your damage and it will show your the name of the monster your killing (e.g) gold slime dominator: XX% (how close you are to moving onto the next weapon title) and the the damage (35%) stating you do 35% extra damage to the enemy. You only get a critical bonus on monsters once you complete a license (you fully upgraded it to the max and it does the most possible damage to that monster). However, at lower levels they don't really believe you deserve a critical bonus so until you start at level 30 and using license I don't think you will get a critical bonus but I may be wrong if anyone wants to correct me and prove it.

The site Ralath gave your really helps. So do read it.