Sorry to keep pestering you gunmaster, but I'm still having problems. I placed the COCmarkerheading in a hallway (I'm assuming you just place on the floor) and then loaded up a saved game and pressed the tilde key and typed first coc vault74a and nothing happened, then I tried COC Vault74a and nothing, then I tried COC Vault74 and nothing. I"m not quite sure what else to do. Thanks gmaster.
I bet you have not loaded the mod with your game.
Well, when you look at the "Cell View" window of the GECK, where all of the cells are arranged by worldspace and there's this list of cells on the left, and you have it looking at "World Space" dropdown named "Interiors", your cell has the "EditorID" listed there for it. That is the thing that is used to access the cell via the coc command.
If that's not working, you didn't tell the game to load the mod, I think? Run the game from the start menu (you need the disk in the cdrom), and there's a checkbox thingie for files I believe and your file should be listed.