Sony Pictures chief Michael Lynton has told a media conference that although 10 million people have signed up to use the cloud-based UltraViolet system that allows DVD buyers to access their movies on computers or mobile devices anywhere, they're not using it enough. Speaking at the D: Dive into Media conference in Laguna Beach CA on Wednesday, Lynton acknowledged that part of the issue is the interface is not as good as it could be. ... It's not easy enough to use. However, he said, digital engineers are working on the problem, intent on making it as easy to use as the ATM. As reported by Home Media magazine, Lynton concluded: The tech part is easy, and once that is resolved, [the rest] will come pretty quickly.