Equiping the arrow: a bug.

Free skill points: a bug. If you have level 1 in Sword Expertise or Augment Damage, and you save and re-load your game, you get a bonus point in each for free.

Polymorph: Yeah, it kind of sucks. I didn't think it counted as a critter on your trophey list, though. Try it on something unique, like the Executioner, and see what comes up on your trophey list.

Buying Finigans Lockpicks: Oooh... Gonna have to do that when I give them back...

And welcome to the forums! Enjoy your stay!