Hi Maaß,
You can still add more columns to views by using the <context menu>|Attributes... item.
NOTE: if you attempt to forward engineer the view, the columns will not be used to generate the views. They are for illustrative purposes only! This is by arrangement with Sparx. When EA reverse engineers a view, it does NOT create columns (at least the last time I tried). Similarly for forward engineering, ONLY the view definition script is used.
HTH,
Paolo