Several unknown props in RVInst

**Describe the bug**
Several unknowns as well as a CS implementation that is needed

**Additional context**
[Source](https://github.com/space928/Omsi-Extensions/blob/7687b6623f5f74b4419695257bd2a4eef54dd93e/OmsiHook/WrappedOmsiClasses/OmsiRoadVehicleInst.cs#L12)