I've searched a lot, but couldn't find an answer yet. But I think, this problem is already known, and maybe there exist some solutions for it?!
If I'd like to view a preview post, which wasn't posted, it won't show the picture, only the text as a tag!
e.g. [singlepic id=791 w=150 float=left] like in the editing-mode...
...when I publish the post everything works fine. So, please help! :-)