Nator's page

In Hero Lab, you can buy an Oil of Keen Edge for 750gp. The item description only says this, "Aura: Faint Transmutation, CL 5, Slot None, Cost 750GP, Catagory: Oil/Potion, Doubles normal weapon's threat range."

That's it, nothing more.

Now the Spell Keen Edge says that its duration is 10 min./level, which would be a minimum of 50 min. Is that how long the Oil lasts or is there a different duration for it?

Does Mage Armor stack with normal and, or Magical Armor? The spell description says that it adds +4 to your armor class, which to me reads like it stacks.
My character has Amulet of natural armor +3
Bracers of armor +5
Ring of force shield (+2)
Ring of protection +2
Add in his Dex bonus of +4 and he has an armor class of 26.
If Mage armor does stack, that will give him a 30 AC.

I am building a hunter character from the ACG and it seems to me that the class does not get any bonus spells. Does the class get bonus spells? Is this class PSF legal???

If I get a new Pathfinder book, can I add Traits and Archetypes from it to to my current Characters?

I have a Tiger as an animal companion and according to the Core Rule Book page 53 says that Acrobatics* (Dex), Climb* (Str), Fly* (Dex), Perception* (Wis), Stealth* (Dex) and Swim* (Str) class skills for ALL animal companions and that an animal companion can have ranks in Escape Artist (Dex), Intimidate (Cha)and Survival (Wis). Why does my tiger get Fly as a class skill (+3 Trained) instead of Survival??? This is especially confusing because Survival is used for tracking and my tiger is trained in Hunting (Attach, Down, Retrieve (Fetch), Heel, Seek and Track).