tailwind there is 4 turn in gen5
LOL that's stupid of me... it says right below in the game descriptions, 3 turns in gen 4 and 4 turns in gen 5. D'oh!
snorlax can learn fissure by breeding
It's listed on the egg move page and on the Fissure page but not on Snorlax's pokedex for some weird reason. And Zen Headbutt is shown there but not on the egg move page... I'll check into that.
cradily can learn giga drain
This is listed on both the Giga Drain page and Cradily's pokedex (check the tabs above the TM section, Cradily only learns GD in generation 4).
and some other problems!
Like what? If you find anything else you can list everything in one question that's fine.