How To Mod HorizonA basic tutorial on how to mod Horizon
can be found hereYou also have the ability to create missions or to disable official ones. Instructions on how to accomplish this task
can be found hereAs with any mod, be sure and carefully follow the instructions and make backups of stable versions so that you don't lose any work.
If you run into any problems just make a post in this section of the forum and someone will get back with you as soon as possible.
Happy Modding