Passing Variables from Storyline to HTML document

Hello fellow designers,

I have come to the community seeking help with a project I'm working on. In summary, I am trying to send 4 Storyline custom variables to a custom HTML page.

I found this great tutorial by Nick Shelton which is very similar to what I am trying to do: https://www.youtube.com/watch?v=cs7qPpN87u4

The problem is, I have a very basic understanding of HTML, JS, and working with setting variables in those environments. 

I actually need a lot less then he provides in his source material. I have no need to pull the user's data from an LMS, or even get the date and time from their machine. 

What I am looking to do is pass 4 TextEntry variables (promptly named TextEntry1 through TextEntry4) to a similar certificate page I made. I have 4 bounding boxes ready to receive the information, yet I can't seem to pass the variables from SL to the HTML that opens in a new window. 

That being said, I'm not much further along than the files Nick provides in his tutorial. I'm trying to get his code to work for me without the LMS function, yet I can't seem to do so. 

With the code Nick provides, is there an easier way to pass this information through? I feel like this should be much simpler than I'm making it out to be, yet there is slim to none support on this subject - one which I think should be pretty basic for web development tools...