The url that you gave does state that changing the notes.ini variable (which is basically what that code does) no longer works for Notes 8.x. I don’t know another method to do that, but what does work quite ok is to tag your text in the language you’ve written it in and then use the normal spell check. Check the text properties box for the language. I agree it’s not ideal, but it’s way better than having to change the spelling dictionary from the preferences each time.