deleting projects in iMovie 10.1.4

To delete a project you click on the circle with three dots in it which appears when you mouse over the name of the project in the Projects window:

However, this only deletes the project database which takes up very little space. The media used for the project are not deleted even if they are from the 'project media' - a that case a new event is created with the old project name. So, in order to save space you need to delete the event/s that contain the media that were used (after moving any media you don't want deleted into other events).

The first thing to do when you want to save space is to go to iMovie preferences and click on 'delete render files' These files take up a lot of space and include files created by projects you have deleted or no longer intend to edit ant further. They will be recreated for any project you subsequently work on.

Geoff.

Geoff - Thank you for the 'delete render files' tip. You just helped me free up 80 GBs of (much needed) memory!