I finally figured out these start point modifiers in multi and I have compiled a long list of codes that will will essentially transform the facility into a different board. All the start points as well as the guns and doors are in the back. The only thing missing is the windows and I can't get some ammo next to one of the guns. If your willing to type these in I think its worth it. If you're too lazy to type everything in you could just do the starting point codes and use all guns or you could only type in half the starting point codes and play the entire facility.

These codes allow for the weapons in multiplayer games to be chosen. Each position where a gun is normally placed can be replaced with any other gun. The guns look like alarms for some reason but work fine. Also the boxes of ammo become proximity mines but you can just use infinite ammo.

Directions

1) Enter the codes, exactly as they are here, in the order they are listed. Only use one of the 3 no clipping codes at a time. And don't enter more than one no clipping code for more than one level, Enter a code only for the level you are going to play!

2) Then, while you are in the level you put the codes in for, stand in any position in the game, then press the L & R top shoulder buttons together! Until you are transported farther away from your current position. Turn around until you see the area you were in, you will be able to see clearly only the area that you were last in, the rest will be transparent. Walk back to that area.. and walk around its edges and shoot the enemies through the walls. You sometimes can't shoot through the wall but if you get close enough to where you gun barely sticks out the wall, then youcan shoot the enemies there. Now to turn the no clipping mode off, you need to go back to where you press the L+R buttons together or at a position in the level that is at the same height off of the ground, this will re position yourself as on the ground level, then walk to the next place you want to use it and repeat this step! The only thing that stinks about this code, is that all the other rooms are transparent! Also, if you wish to use this on a room that has the same floor level for the most of the area, try climbing up the stairs a bit and press L+R, but, just remember that you have to be back at that same position on the stairs to turn the no clipping code off!

3) A tip, when using this code, be sure to use the following code 80069669 0001 and go into the cheat menu and turn on the code that says NO NAME cheat, which is the DEBUG MODE code, it will tell you what room you are still in and it will show you your coordinates, this will make it easier for you to get back on ground level by remembering where you last were before by the coordinates! Also with this code, it will sometimes put you in a position of which you can't get out of, you will have to simply EXIT the level and start over!

4) NOTE: I also have the Y coordinate modifier code, but it is REALLY glitchy because it not only modifies your Y coordinate, but it also modifies what room you are in, and it will take a little more time to get that code ready!

5) Just Added, a third code to each code, this is the Panic button code, a code that will let you move positions if you get stuck, press the Cheat Device Button to go a different position in the room, and hopefully if you can alternate between the L+R and the Cheat Device Button you can get back on track!

Remember: You have to press the L+R buttons to activate these cheat codes.