thanks all the hints you gave me, I have tried and discovered a little and searched for some reactions.
The display "problem" of blank.gif I simply cleared by using another blank.gif as the default. I was a little to scared to go into a working system and php stuff.
It seems that if there is a html code used which uses the "align" within the first 200 signs that code is used also for the general display of the shortcuts of the downloads in the list. If there is just used <p></p> everything is fine.
The pyramid layout comes from adding "align=center" (or left, right...) next, and next.
This problems do not arise if the editor BBC is enabled, but the display does not produce any html out of the BBC design but shows the text simply like it is.
The general funktion of the 3 various possibilities of editor "No" "BBC" "html" is not clear for me. Some seems to be used as producing tool, but some have sudden impact of the display as well.