Kilgore Trout, when you modified the file yourself, did you use a text editor (like Notepad, notepad ++, etc.), or a HEXADECIMAL editor ? (displaying series of two characters, like '8F 2C EA 87 A8' ?)
Because, if you used a TEXT editor, considering that the feat name had a NEWLINE character in it (and that the NEWLINE is treated differently whether you're on a MAC, Windows, or Linux system), that's likely your problem, here. So, I'd advise you to use a HEXADECIMAL editor instead, in order to change precisely the values to those needed.
The "NEWLINE" character is value 0A, and lower-case letters will be 61 (for 'a') to 7A (for 'z').