When you have a fully functional world with Crazy Craft (or any working addon), (including the world file and the resource/behaviour packs). Store that backup in a separate location. If an update breaks everything, you can restore the backup and continue playing on the older version.
Look for a reliable source that offers a .mcworld file (which is easier) or a combined .mcaddon file. crazy craft addon mcpe patched
Your first goal is to find armor. Vanilla diamond gear will not protect you from the mobs in this pack. When you have a fully functional world with