I put the Aim ability in the Item Abilities but when i press right click, the player rotates but doesnt run the arms animation, but if i try this in the demo scene it works, why is this happening?
Are you in a third person or a first person perspective? Did you replace the animations? If you are setting up a new item you can follow one of these videos:
Since you have your own system it makes it extremely difficult for me to debug. In your situation what I would do is create a new ability that works with your system: