Complex sentence: Originally the studio wanted to sell the cars and tracks as advertising space much like in the real world; but because of the company size, and being the first release of any product like this, the studio was unable to fill any of the advertising slots.
Split into simpler sentences: Originally the studio wanted to sell the cars and tracks as advertising space much like in the real world. But because of the company size, and being the first release of any product like this, the studio was unable to fill any of the advertising slots.