Update README.md

Author: HielkeMinecraft

README.md

@@ -1,7 +1,20 @@
 # Open Minecraft Note Block Studio
 An open source continuation of Minecraft Note Block Studio. 
 
-## Custom Features:
+
+## Download
+You can download Open Note Block studio [Here](https://github.com/HielkeMinecraft/OpenNoteBlockStudio/releases/latest).
+You can either download as .exe (recommended), or as a zip file.
+
+## Issues:
+For issues, please head over to the [issues](https://github.com/HielkeMinecraft/OpenNoteBlockStudio/issues) page.
+
+## Contributions:
+This project is written in Game Maker Language (GML). You must have GameMaker Studio 2 in order to open this project and make changes.
+
+For contributions, please open up a [pull request](https://github.com/HielkeMinecraft/OpenNoteBlockStudio/pulls).
+
+## Features:
 
 ### 1.14 Note Block Support:
 Open Note Block studio supports all 6 note block sounds added in 1.14!
@@ -22,14 +35,14 @@ Datapack export also has an option to allow nearby players to hear the music too
 When using Note Block Studio late at night, you might have wondered: why are my eyes burning?
 Well wonder no more! With dark theme you can compose all night long!
 
-## Download
-You can download Open Note Block studio [Here](https://github.com/HielkeMinecraft/OpenNoteBlockStudio/releases/latest).
-You can either download as .exe (recommended), or as a zip file.
+### Changed .nbs format
+To make Note Block Studio work better in the future, the .nbs format has changed. 
+The first 2 bytes (used to be song lenght) have been changed to 0 to indicate the new format. 
 
-## Issues:
-For issues, please head over to the [issues](https://github.com/HielkeMinecraft/OpenNoteBlockStudio/issues) page.
+After this, the next byte is the .nbs version. Right now that version is 1, but if the nbs format needs changes in the future, it will be different.
 
-## Contributions:
-This project is written in Game Maker Language (GML). You must have GameMaker Studio 2 in order to open this project and make changes.
+The byte after that is the first custom instrument index. 
+**Example**: If there are 10 'normal' instruments, 10 is the first index of the custom instruments (remember, we start counting from 0).
+
+The rest of the format is the same, with song height being the next short.
 
-For contributions, please open up a [pull request](https://github.com/HielkeMinecraft/OpenNoteBlockStudio/pulls).