As ktom says in the thread you're linking to, 0 *is* included in "any number", but that's not the point. The point is that, to quote the FAQ, "If a card uses the word "then," then the preceding effect must have been resolved successfully for the subsequent dependent effect to be resolved." A standing effect cannot resolve successfully if no card is going from a kneeling to a standing position. Easy as that.
Also, the "if able" on Game of Cyvasse has nothing to do with this. If it wasn't there you could only play Game of Cyvasse if all players control at least one character with an INT icon. The "if able" gets around that. It has no bearing on the standing/kneeling situation.
You can choose a kneeling character for Game of Cyvasse, but since no actual kneeling happened (no character went from a standing to a kneeling position), you can't win the Game of Cyvasse.
Young Griff is a bit different, because there is no target (no word "choose") but the principle is the same. Technically, 0 is included in "any number", but if no card goes from a kneeling to a standing position, the pre-Then part of the effect is not successful, and the post-Then part doesn't happen.
As for the calls for an erratum - really? A 3-for-3 tricon with stealth who can stand your Street Waifs, Maesters and Lanni Kneel victims, and it's not good enough for you?