Quit the editor (if running)
Locate or create a folder called Plugins inside your project’s main folder (next to folders like Content, Saved, etc.)
Unpack the PointCloudPlugin inside your Plugins folder
Re-open the project
Your directory structure should look similar to this:
Note: During the first run after installation, the engine may need to recompile new shaders - this may take few minutes. Any consecutive run should be as normal.