To activate the spoiler you need to install EPM v1.4 The spoiler is activated automatically when the car is moving at high speed.
After installing EPM v1.4 and a car, you need to find out the serial number of the car, which can be obtained during the game while in this car and pressing the Num 8 key. When the value is received (in the upper left corner of the monitor), without turning off the game, minimize it and enter the folder with the game installed along this path scriptsmovedoors.ini. Then find this line: XXXXXXXXX,2,25,20,U,J,1,1,0,0,3,0.05,1,50.0,0,0,0,0,0,0,0,0,SLSAMG by WWTT and instead of XXXXXXXXX enter the resulting order of numbers.
Attention! If such a sign "-" (without quotes) is indicated before the numbers, this means that it will also need to be entered.