answering the second question first:
ThingWorx View is supported on iOS, Android and Windows 10. There are links to the apps in the corresponding stores on the https://studio.thingworx.com/home/ page for which you have a login when you're part of the TWX Studio pilot/trial program.
I personally used iOS and Windows 10, the later with my laptop and a webcam and that worked fine. Can you provide details on the hardware and Windows version of your Surface tablet?
Regarding external content in Thingworx Studio Experiences: right now we support external content for images (URL Image widget) and via the Hyperlink widget.