How to install them:
1) Download brushes.zip and extract the files inside into any folder;
2) Open the editor, go to the "Tools" tab, then Settings - Obstacle Brushes - Import Brush;
3) Go to the folder where you extracted the files and select them in the order you want them to appear in the editor's brush list.
I hope someone finds them useful. If you have any questions or find any bugs, please let me know in this thread.