Full screen preview doesn't work on external monitor unless system-wide scaling is at exactly 100% in Movie Studio 15 Platinum, otherwise the video is cut off. The preview works fine on the main display, but not the second, this happened in 14 as well. I can see all of the correct information in the "Preview Device" tab in preferences, Before anyone asks, I've looked through posts about this from about 2 years ago and made sure my drivers and .NET framework is up-to-date. I'm running on a mid-tier Windows 10 desktop and can provide anymore information necessary, thanks!