First, you'll need to have Autodesk ReCap Photo installed in your computer. You can download the free-trail version from here and you can continue to use it for a number of things even after the free trial ends. You will only lose some of the "Pro" functionality.
Follow these steps to create the walkthrough video:
1- Download your Mesh file from Site Scan - either RCM or OBJ (RCM is the native ReCap Photo file format but you can also use an OBJ file).
2- In ReCap Photo open your mesh file
3- Go to the Export section - tool bar on the left side - select "Video"
4- Select the video settings:
Video Format: Either AVI or MKV.
Resolution: The higher the resolution, the higher the file will be.
Background Color: You can select any color that you want for the background.
Display Mode: I would not recommend modifying it.
5- Select the type of video you want to use:
Turntable: Creates an orbit-type of video along the ring in blue shown. Select the total time you want the video to be and click on Export.
Key Frames: Allows you to manually zoom in to specific angles, save it as a "key frame" and move to the next one (do so until you have captured all the key frames that you want for your video).
Select your Key Frame Interval and click on Export.
Here's how the results will look like.