I downloaded a trial version of Presenter 8 and testing some of its features. So far it looks great but i'm unable to customize the player properly.
Ideally I would like to change the next/previous button to another design (not just an arrow), also be able to change the attachment button to something more meaningful to us (like references)
Is this at all possible?
Not really possible in Presenter. You may want to consider Captivate, as the player skin is more customizable.