Weapons on Defenders?

I have a question or 2:
1. "Before the fight registration they have to be fixed"! In other words: before I register for a day?
2. Let's say I set Carl Yumi Maggie and give them fire pistols! In the course of the GW (e.g. HF) I take away the fire pistol because I need it for something else! Will Carl still wearing the fire pistol in the GW?