3D Systems' preliminary Q3 report arrived with news that's worrying investors.3D Systems (DDD -22.59%) stock is plunging today following the publication of the company's preliminary third-quarter results and update. The 3D-printing and engineering specialist's share price was down 22.5% as of 11:45 a.m. ET.After the market closed yesterday, 3D Systems released preliminary Q3 sales results. In addition to the revenue preview, the company also announced that it would be delaying the filing of its quarterly 10 ...