DEAD RISING 2: CASE ZERO

-The first locked door is the Sheriffs. To get to it, Climb over the dumpster next to the pawn shop. Follow the path around the back until you reach a door. Inside that building, open the door to your right, that is the locked door.
-The second locked door is Bob's Fish n' Hunt.To get inside, Climb up the dumpster and onto the roof where Bob is. From there, go to the left side of the roof, jump over the gap to some stairs, then jump the gap between the roofs. On the left from where you are facing (go forward to the edge) you can get across to the Fish n' Hunt roof. There is an opening in the roof, you can jump down into the store and open the front door.
-The third locked door is the back door of the Theater. Go into the theater (next to the barbershop). Go through the screen room and there will be a back door to the right side, simple enough to see.
-The forth and final door will require you play a bit of the game. Play until you save Dick, the pawn shop owner (I hope it's not a pun ¬_¬). Buy a hint from him (this will get you an achievement if you don't have it) and he will tell you about a key to a shed. This shed is the last locked door. Go to the roof with Bob, and jump over the gap to the stairs, but this time go through the door on the stairs. Inside, go to the farthest room (round the corner) to collect the key. Then, go to the watershed (between the hardware store and a closed green building). Open the door, now that you have the key, and the achievement should unlock!

There are 5 total doors, you must unlock all of them:

1 - Movie Theatre - Find the movie theatre and walk through it until you exit out the back (you must do this to get a part either way).
2 - Water Shed - First get the key, in the upstairs section of the hotel. Go to the alley near the gas station, and onto garbage dumpster, jump onto the roof, and then follow it until you can reach the staircase leading to the second story of the hotel (facing the alley). Walk in and the furthest room, you will find a key. Take the key and walk down the street to the shed next to the bowling alley (closer to the quarantine zone).
3 - Pawn Shop - Find Dick on a van outside your safe house. Kill the zombie's near it and have him take you to his store, once he opens it, that will count as a door.
4 - Sheriff's Office - Climb the dumpster near the Bowling Alley ("Crumpeydog"), and then jump over the fence. Follow the alley, and you end up at the police station. Walk out the front door for this to count.
5 - Bob's Finsh 'n Hunt Store - Climb the dumpster in the alley close to the gas station, jump on the staircase, (as if going to the hotel) and now jump across the alley (to the other side). Get on the roof, and go to the direction of the department store. Stay on the roof and go towards the gas station, you will end up on a roof (across the alley from where Bob is shooting Zombies, and fall into the hole in the roof. Exit out the front door.

1. Hunting Store. Climb up the fire escape behind the hotel, jump across the alley, turn left across the rooftops, enter the building from the top and unlock the door from the inside.

2. Movie Theater. Head into the movie theater, head for the actual theater, open the side exit door into the alley.

3. Shed. Collect the key in the hotel (Ready to Ride achievement), open the shed for the Bike Forks.

4. Police Station. Head to the alley between the bowling alley and the pawn shop. Jump the fence, hang a right and at the end of the alley is a door. Open it, enter the station and then open the front door.

Door 1 : Sheriff's Office - After the pawn shop next to the bowling alley hop on the green bin and over the fence. Go through the only door there and then open the front of the office (there is a shotgun upstairs on a desk)

Door 2 : Shed - After speaking with the guy in the pawn shop he's told you about a key. go to the alley behind 'Momma's Diner, there are some stairs that don't quite reach the ground. You CAN get up this way, but I found it took several attempts before he climbed up so the easier way....go further down the same alley behind the Casino. Jump onto the green bins and then jump twice more to reach the lower roof then pull yourself up. (this is the roof bob will be stood on) Stay to the left of the building where there is a wire fence, jump up the next small section and go to the far top left corner. Standing at the edge you will see the stairs infront of you. Jump accross and into the door, head left and go all the way round to the right, in this room is a key on the floor for the shed. While we are in here we're going to open door number 3 which is Bob's Fish 'n Hunt store. Come out of the room with the key in, there are 3 windows in the corridor, climb up through one onto the roof. Head left and you'll see a walkway, drop down and cross it. Jump up on the ledge to the right where there is a helmet, walk to the left of it and drop down onto the ledge, stick to the wall and jump up onto the roof. You'll notice a hatch is open, drop down and open the main door.

Door 4 : Movie Theater - Easiest one, walk through the main doors, into the seating area and open the exit door on the right. From here you can go to the shed so you have all 4. The shed is next to a pile of big wheels. If you look on the map, bottom right corner, its the 2nd green box in, a lot smaller than the others.

I hope this helped and I didn't go on too much, tried to keep it detailed enough so people knew where I was talking about