The Frogatto editor is great. There’s a lot you can do to find and place objects and tiles on the level. But there are also a lot of properties that are not available through the user interface. For these properties you have to open up a separate text editor (or the in-game text editor) and add the code manually. I like using notepad++ and vim because I’m familiar with them and they’re very powerful, but there are some advantages to using the in-game text editor. With the in-game text editor you can see your changes take effect immediately and it will show you any errors that result from the code as you type them so you can correct the errors before running into any assertions or mysterious crashes. This is particularly good when you’re dealing with animations. But for most other things I’ve needed to restart the program to re-run the code anyway and I find it easier to just use an external text editor which preserves my edit history.