I've been using Inventor Fusion for awhile and I wanted to load my file into the Fustion 360. I new it had to be possible but the complete lack of an add button meant I had to go look at a video to find out that you add an existing file by drag and drop to the open project. Note, an overlay comes up saying you can drag and drop into a closed project but this didn't seem to work on OSX.
Conversely, when I needed to export my STL, it took a video to help me find the almost hidden export menu in the designer. I would have expected to be able to export from the project list.
I'm OK with how it works now but the complete lack of UI cues and the need to watch a video to find something so simple had me scratching my head for an hour.