where? i have created a new image and like perks i have added

image,t7_hud_zm_powerup_giant_deathmachine

Inside APE you need to search deathmachine there will be a material and an image  ...

the minigun powerup shader dont work for me

What issue are you having? The minigun is already made in APE so you just have to edit it there.

You can go here and join it. https://discord.gg/2ePrB

Weapon costs are handled on the trigger or in the weapon file, can't remember which but that is super simple to edit. As far as the guns yes you would hand to use maya. If you are on the bo3 discord add me I am noobforlunch on discord. I will help you out.

For the guns you would have to add them yourself as they aren't loaded in giant. Then after that you would make a custom weapon file. The weapon file is found in share > raw > gamedata > weapons > zm after this you go to a map that has the weapons you want and export their animation...

This will work for powerups, as far as hud goes all we can edit currently for images of that is the DPAD.