Once the BWA is loaded with the data, you have to open Explorer and go to the "Manage Spaces" menu at the top menu. This opens the Manage Spaces Tab where under the "Business Warehouse Accelerator" node, all available cubes are listed, including the one created and named in Index Designer.
By selecting that Cube all created Information Spaces are shown, here one was created already, and by clicking on the New button, another or a first one can be created.
Just two tabs are important, the Information Space Name in the first tab...
...and what attributes the Information Space should contain.
With that done, the all that is left is to index the Explorer Information Space - the most right button.
Now the Home screen will show this new Information Space - possibly after an refresh of the list - and we can start using it.