In the past months I barely had any spare time since there was much work for school to do, so I toyed with the idea of releasing the source of my project. Originally, I planned to release it long ago, but canceled the idea since there was much work left like commenting the code, making it suitable for open source and thinking about a license.
I finally, after a comment from AsuMagic, did all this so anyone who wants to improve / modify my project can do this now!
The project is licensed...

[Open Source] Map Editor 1.3.1
A simple yet powerful Map Editor for King Arthur's Gold! Officially discontinued but Open Source!