The mod opens an additional "Special" option in Need for Speed ProStreet, in the "Vinyls" section. This means that you can apply any AI vinyl (like those of your bot opponents) to your car, from 355 options.
Not every livery option is suitable for a specific car! But, after applying it to your car, you are given the opportunity to adjust the vinyl (move, stretch, reflect, rotate). And somehow the selected vinyl will look beautiful on your car, almost perfect. You can also add additional layers to this.
The "Special Vinyls Unlocker" mod was made for Need for Speed ProStreet to open additional vinyls (liveries). And if you use an image editing program (Adobe Photoshop, Paint.NET) and draw your own, save it in the desired format? Then, using "NFS-TexEd", a texture pack editor from ProStreet, you can choose any and replace it with your own artificial one.
To install Special Vinyls in NFS ProStreet, which opens an additional option for selecting vinyls, simply move the "scripts" folder and the "dinput8.dll" file to the game folder.