How to get liveries to work AND how to fix ZLIB20 error with modded cars

I found out how to get liveries to work & I will show you how to AND how to prevent constant crashes from ZLIB20 error, caused by the latest OPENIV update

To get liveries to work first you need a car that matches the livery you want to put on it, as different authors use different templates, so check the read me to see what specific car your skin is optimized for. Then Open SparkIV, install the car (if necessary). Then click the texture file and click edit at the top. Then when you are in edit mode, click one of the ''police_sign_1'' or something similar. Then click import (make sure that the skin is on the desktop). Find the skin and click open. Then if you are using Simple Native Trainer, go to it's INI and put default livery to 9 (only if using multiple liveries). 

To fix ZLIB20 error, you will first want to replace your vehicles.img with a fresh backup. If you didn't backup, then the only option is to reinstall the game. Then use SparkIV to install any cars you want using SparkIV as the latest OpenIV update has made any cars installed through it, crash GTAIV.