Nebulous
Legend
Regarding the Tzeentch's Curse rules, from what I've seen and read in the core book, anytime the dice you roll to cast a spell come up doubles, triples, or quadruples, you get a nasty magical backlash, with the result of it rolled on a special table, and the more of the same number you get when casting, the worse the potential backlash. It's actually explained pretty well (I think) in the core book.
Yep, that sums it up. The table I REALLY like is from the Realms of Sorcery, the potion spoilage table. Unlike D&D, Warhammer potions only last for a limited number of season, 7 at the most a think (roughly a year and a half?) before they're fully spoiled. Drinking a potion can have a wide berth of effects from Bad Breath to Death. I love it actually, and i'm incorporating that chart into my 4e campaign.
Damn, i really want to play WFRP, but it will be hard to convince the players anytime soon. Maybe i can find a secondary group...