No need to do any editing works !
Since this feature was, it was immediately introduced in the next version.Please use the latest version.
All you have to do is,
1. Get the new version
2. Enter the Post ids where you don't want in the textbox given in the widget
3. Save it.
That's all. As per the request, this feature was immediately taken under consideration in the next version.
The new version was released on 2010-8-9 itself !