DYOM IX is the continuation of most famous Design Your Own Mission mod, created by PatrickW and Dutchy. V 5.2 version is officially out, and here are the changes:

Fixed Ped Spawning. Ghetto for ghetto people, city for urban, expensive and cheap cars
Added 3 new types of camera shaking in Cutscene ?
Added a feature for Vehicles so that it must be in the checkpoint, and not the Player ?
Added the feature to attach a magnet to helicopters ?
Trains no longer float in the air after setting
Added a feature for Actors so that he must be in the checkpoint, and not the Player ?
Added a feature for Vehicles, now you can turn on the siren ?
Fixed some cutscene bugs
Air traffic now changes with Ped/Traffic settings and Objective
Added 27 new skins for Actors (Added custom cutscene.img to put there reworked and stable skins)

Visit GTAForums page of the mod, give suggestions & ask for help if you need one!https://gtaforums.com/topic/981899-dyom-ix-modification-for-dyom