GameMaker Text Box

Since we're making our long term project in GameMaker Studios, I've been making a basic text box function. It's not at 100%, but here's a preview. (Keep in mind this is with no assets or sprites added: its just the text box.)


And also a tutorial link, although the code shown will need some modification.
https://www.youtube.com/watch?v=HdJ0ZUIs-AI