Nothing, all you would have to do is convert it to a .txt file which is a built in feature to it. Then save it as a .cs
Actually, you're stupid.
You can just save it as LOLSAVETHIS.cs and it'll do that, no .txt extension.
If you're having problem with rich text vs. raw text, you can change this with a preference. What's the difference? Open up a file from a working addon and see if it looks like what you've got.
Also, make sure you aren't just rightclicking and compressing the folder. You have to highlight the contents and compress them.