There should be 2 windows that open when the game starts: the game and a terminal that shows error messages. Is there any messages on the second window? If so, I'll need to know what they are to fix it.
If not, then I'm guessing you added it to the mod before or after applying it. If you added it to the mod after applying it, then you need to re-apply the mod.
If you added it to the mod before applying the mod, then the problem is probably the formatting of the text added. The text provided in his post is not the literal code. The first part is to be included in "spelllist" and the second part is a function that goes in any black space towards the bottom of the file. Both parts will have spaces at the beginning of the lines where the game will expect tabs. The vanilla mod system is very literal and will ignore changes that do not exactly match its expectations.