Sorry for delay. I had to figure out
The plugin works as described in the manual.
But SketchUP changed term "Plugin" to "Extension".
Right directory for SketchUP 2017 is "C:\Program Files\SketchUp\SketchUp 2017\ShippedExtensions"
You can just copy videocad.rbs to this directory and restart SketchUP, as described in the manual of the Plugin.
Or you can make a folder "videocad", place videocad.rbs to the folder and zip the folder.
Then rename obtained videocad.zip to videocad.rbz
After that you will be able to add this file to SketchUP as an extension using Main menu of SketchUP>Window>Extension manager>Install extension
You can also download the plugin for the second time and find videocad.rbz with additional instructions in the archive