Unless I am doing something very stupid the source package available for download (Unity_TowerDefense_Project_Source_Files) doesn't resemble the package shown in the video. There are none of the scenes mentioned in the video only the assets. Is there somewhere else I should be looking for this file so I can follow along as described in the Setup and Building the Towers section?
All the scenes are in there but in Unity 2018 it seems it requires importing each scene specifically. If you double click the scene file (it'll have a Unity symbol on it) for the lesson you can then import it again. I'm not sure why it does this, but I'll try to update the files for use in Unity 2018 to avoid this. Thanks for letting us know.
Ok so the issue persisted within Unity 2017 as well, really don't know why the scenes needed to be imported separately within the project. I exported everything and reorganized the folders and it looks to be working fine upon importing into a new project. It contains all the completed scenes but should be working now. Let me know if you continue to run into issues using the files.
Thank you Jonathan that new project unity package has sorted it. Appreciate the support and quick resolution