Yes, I have done that, but for some reason it isn't doing anything

Hello,

I have been trying to use the chevrolet impala as a cop car using the addon_vehtypes, but I can't get it working in game. And mm2gl says it has the following conflict:
aud/cardata/shared/vehtypes.csv -> MM2GL share file
does anyone know how I can make this work

I have added some cars to my MM2 version, and now i would like to put some flames or other paintjobs on the cars. my question is, in which programme can you make them, and how do you add them to the .ar file of the car