I have a question because I am totally stuck on this one.

When I place structures and units on the map and assign them to the starting player (it seems to be player 7), I cannot see the structures nor units on the map once saved.

The only thing I was able to do is copy-paste some elements.

I use the "Build List Tool" but having no luck at all. What am I missing here?

Ok my bad, found that "place item" should be used not "build list tool". Now it works as expected.