The game is SP mainly always will be.
The MP side is not like the 3rd Party Truckers MP mod where you are will alot of people.
This is an official add to the game which will allow you to play with up to 8 people.
The trainer is for and only for SP if you talk about using it on MP side you will be warned. We do not condone the use of trainers on any form of MP coop local lan.
They are not designed for this and you will not get any help for this either. Asking assistance on the Convoy side of this game only gain you a warning.