My advice would be to remove all the stuff you’ve added, see if it works normally, then one by one add things so it’s easy to keep track of, and not bomb rushing and installing 10 things at once before starting the game. Keep it simple, then add slowly. I’ve had to delete and reinstall my game several times, you will learn and get the hang of it. NVE had a bug on initial release of new update with that error occurring, the authors corrected it a couple days ago, not sure when you downloaded the NVE SP package but that COULD be a cause. Sounds to me something happened or is missing that has to do with addon vehicles aka missing prerequisites such as gameconfig etc. I would start by removing the dlc and all the stuff you added to allow you to use the DLC pack.