"MediumCar" is missingSolved
Hello, "MediumCar" is missing in the config file
Here is what to add directly to the .cs file .
Remember to remove the config and lang file before making this change.
Like this from line 1883 just before ["LargeCar"] in .cs file:

["MediumCar"] = new ModularVehicleS
                {
                    purchasable = true,
                    displayName = "Small Modular Car",
                    distance = 5,
                    usePermission = true,
                    permission = "vehiclelicence.Mediummodularcar",
                    commands = new List<string> { "medium", "mediumcar" },
                    purchasePrices = new Dictionary<string, PriceInfo>
                    {
                        ["scrap"] = new PriceInfo { amount = 1600, displayName = "Scrap" }
                    },
                    spawnPrices = new Dictionary<string, PriceInfo>
                    {
                        ["metal.refined"] = new PriceInfo { amount = 10, displayName = "High Quality Metal" }
                    },
                    recallPrices = new Dictionary<string, PriceInfo>
                    {
                        ["scrap"] = new PriceInfo { amount = 5, displayName = "Scrap" }
                    },
                    spawnCooldown = 7200,
                    recallCooldown = 30,
                    cooldownPermissions = new Dictionary<string, PermissionS>
                    {
                        ["vehiclelicence.vip"] = new PermissionS
                        {
                            spawnCooldown = 3600,
                            recallCooldown = 10,
                        }
                    },
                    chassisType = ChassisType.Small,
                    moduleItems = new List<ModuleItem>
                    {
                        new ModuleItem
                        {
                            shortName = "vehicle.1mod.cockpit.with.engine" ,healthPercentage = 50f
                        },
                        new ModuleItem
                        {
                            shortName = "vehicle.1mod.rear.seats" ,healthPercentage = 50f
                        },
						new ModuleItem
                        {
                            shortName = "vehicle.1mod.flatbed" ,healthPercentage = 50f
                        },
                    },
                    engineItems = new List<EngineItem>
                    {
                        new EngineItem
                        {
                            shortName = "carburetor2",conditionPercentage = 20f
                        },
                        new EngineItem
                        {
                            shortName = "crankshaft2",conditionPercentage = 20f
                        },
                        new EngineItem
                        {
                            shortName = "piston2",conditionPercentage = 20f
                        },
                        new EngineItem
                        {
                            shortName = "sparkplug2",conditionPercentage = 20f
                        },
                        new EngineItem
                        {
                            shortName = "valve2",conditionPercentage = 20f
                        }
                    }
                },​
You have to put them in manually now

Merged post

https://pastebin.com/TDhps4tY

This is mine to get it back to what i had... VIP cooldowns are 0 though... just so you know

yes, I even made the change in the plugin directly ... see my post above.

After it is true that we can only add it in the confi file, without touching the .cs
It's actually easier for those who don't like to touch .cs
I saw, but I posted the conf up anyway for people that wanted the original setup and are not "the best" at configs :D includes the chassis spawns too
You can add more modular vehicles in the config, not just this
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