A very small but annoying detail for every starter.
After installing ETS, you do not have the buttons to open a new window (Topology, Building, Group Addresses,...) in the toolbar by default.
I noticed most of the laptops have sufficient screen resolution, so why not have them by default?
Also when you want to add them, it's very hard for someone who doesn't know how.
You need to drag the button exactly to the right of the last separator to be able to release it.