Ok i will change a little bit, the most stuff was attached to a big polygon.
The Big Polygon was also the only thing on the undercarriage that got a collision layer, to minimize lags.
But I can change that...
For the beginning,start with downloading scenes from other users and try to remake them just to understand how they work...
But dont upload them if they are just copies of the Originals...
And make sure that the Title of the scene and your scene fit together...