Here's the error when I just open the file in game maker. Also I should note, I'm pretty new to game maker and I could just be doing something wrong.
Then I'm stumped :(! It definitely comes up for me as an existing function (you can middle click on a function to bring it up in the documentation).
Though, I've done some googling and noticed that it's listed in GMS2 as a new function... perhaps they only recently added it to 1.4 as well? So the only thing I can think of at this point is to make sure you've installed the latest version of GMS1.4.