First hurdle, I got a key, says I need a key

[DrolDraw]

So I'm right at the very start of the game, I killed a corpse and got the key, the help on the key says all I need is the key in my inventory for it to be used, yet when I click on the gate it says I need a key.

Help!

[figmentPez]

You're trying to use the wrong door. In that first room there are multiple exits, and the key you get off a zombie only opens one of them.