Video missing after using Long Video Classic Plugin.

Hi there. A bit of a newby here so bear with me. I downloaded and installed the Long Video Classic plugin on my Theta V camera and everything seemed to work as it should. I recorded a short video using instructions from the web page but when I went to view it, there was nothing there on the camera. The camera says there is 18.3GB available on there but I can’t see anything so is that a usual figure to find on there? The only thing I can think of is that I am using Windows 7 as opposed to 10. Can anyone shed a light. Thanks for your patience. Keff McCulloch