Is the drop rate, of the book, or the spawn rate of the black kat affected by the the difficulty?

Is the drop rate, of the book, or the spawn rate of the black kat affected by the the difficulty?
Also, if I farm the daily mission is it possible to get the book from there?

No matter what difficulty you do, you'll still be able to get the loot from the black kat. If there are any levels with a black kat, they have a chance of dropping a book.

Is this for sure? I need to grind as much as possible, I can't miss the event or waste my time.
It is also said that black kats won't have drops In predetermined locations what does that mean?

The book is just like any other rare material. So there is a good chance that it will drop more often on elite than others.
Black kats in predetermined locations do not drop any loot. The only predetermined location to my knowledge would be on that mold and black magic.

@Fehzor
so the books are more likely to drop on elite mode, but what about the conversion rate of kats?

The book drop chance is supposed to be 1%? uhh.. would difficulty really increase those chances? So, is the 1% chance for normal mode?

I don't care anyomore, I FOUND THE BOOK TODAY!
No kidding. I swear on my Warhammer.
IMA graveyard this, but I can't now due to a bug.
I don't think the difficulty will have to do anything with that but i may be wrong.
And yeah you can farm 8-1 missions i think it is, in hope to encounter a black kat :)
Good luck!