No extra_english.lang

[richm0nkey]

The notepad way is one way but if I am not mistaken there is actually a program that comes with the map editor, model editor etc called HplLangTool.exe. Just make a blank txt document in your story's root and make the .txt portion say .lang instead. Open HplLangTool then use that tool to open the .lang. You might have to find more tuts on how to use the tool the right way but it will more or less likely be easier than typing the whole thing out.

[EDIT:]
Make sure the lang file is named extra_english.lang :3