Tree editor has black text on black background

[slmeyer]

After creating a new map without a default map, the tree editor is unreadable, because both text and background is black. I could not find any instructions about how to change this. other maps work well

[insilmaril]

Two questions:

a) why is there no default map? b) Can a MapCenter be selected in MapEditor and be colored? If so, does it change color also in TreeEditor?