@RD3 Try installing version 2018.7.7 or 2018.7.6.
Do not click on the download button because that will install the latest version and that version doesn’t work.
If you want to manually install it then download the package from here: https://dynamopackages.com/download/528038ad3f7315936f000058/2018.7.7
Extract it in a folder (optional: rename the folder to LunchBox for Dynamo)
Go to %appdata%/Dynamo and locate your packages folder and copy it there.