I am new to Dynamo and have just installed it. I was watching the Dynamo for Revit Baby Steps for Non Genius talk on YouTube: https://www.youtube.com/watch?v=0iq8hIk9NSw&t=428s and trying to follow what they did. However the first task: Search for Wall types does not work. I have Revit 2018 running at the same time. Can anyone help?