Hello guys,
here you will find all solutions that you need.

POWER DOOR
============
to open the power door on the roof you have to find the hammer.
It's on a table next to Widow's Wine.
When you get it, go to the door and press "use button".

PACK A PUNCH DOOR
==================
to open the pack a punch door you have to feed all soulbox (the five teddy bears).
Location:
1) At the parking, below a lamppost.
2) At the parking, in front of a car with lights on.
3) At the ground floor, in the Stamina-Up room.
4) At the second floor, in the Speed Cola room on a seat.
5) On the roof, at the eletrical area on the left

SHOOTABLE EASTER EGG
=====================
when you get all bottles you obtain a perk (eletric cherry).
When you shot on a bottle you get a message and 250 points.
You have to find 3 bottles.
Location :
1) At the parking, in the burning car next to Quick Revive.
2) At the first floor, in the Double Tap room, on a shelf.
3) On the roof, at the electrical area, in front of the shield table, just behind a fence.