This is not a bug.
Missions no longer rely on AP for success, but on several hidden parameters concerning your units.
Most of the time, they -try- to reflect some sort of logic related to the theme of the mission (for example: getting mana gems is much easier with a magician than with a warrior who knows nothing about arcana).
We are pretty sure you will all figure these parameters out very fast, but we hope you'll have fun while doing it
