Thanks for the nice support, even though my discription was rather confusing, not to say totally turned top to bottom.
Editing now works fine with WYSIWYG editor off. Which is what i want for my current project.
Btw you might be interested in the fact, that if the WYSIWYG Editor is turned on, one of my text widgets makes problems, if i hit enter, nothing happens, no new line is added. But you can erase lines. I did copy and paste an empty line and pasted it in, and that works. Strange …
My mistake: the problem is editing text widgets with WYSIWYG Editor off.