Forza Horizon 4

Setup

1. On main menu, press Continue, as you cannot change telemetry settings into this menu
2. Leave garage
3. Press Esc to open settings
4. Enter Settings > HUD and Gameplay > scroll until last 3 options
5. Change the last 3 options: set DATA OUT to ON, set DATA OUT IP ADDRESS to 127.0.0.1 and set DATA OUT IP PORT to 5300

Start and close automatically on Steam

1. On library, right-click on Forza Horizon 4, then click Properties
2. In general, set on Launch Options "C:\Path\To\RacingDSX.exe" --nogui --exe-attach %command%