I have a Lenovo Yoga 900 with i7 processor and running Win 10. I run, when at my desk, a second monitor, a Dell P2715Q, via USB-C port and a Display adapter and at 4k res in Extended Display mode. It works perfectly with all other programs so far, including Photoshop Elements 15, but with Premiere Elements 15 when I drag the editor window onto the external monitor and attempt to resize to fill the screen with (not playback of the video in full screen) it just jumps back to the smaller monitor on the laptop (also set for 4k). It will only work there at a given size no resizing even if reducing size. I want to use the editor on the large screen as it is fiddly on the smaller screen. Any solution to what I see as a major bug.