Any way remove grouping from Report Navigator?

Hi Alll,

I tried to remove grouping from Report Navigator in SRB design view and 
failed.
Somebody know the way for it?

I created a report, or open any report add new grouping remove grouping later, 
the dummy Grouping remains in Report design view, and I can not remove it.

The reason why I trying to do this, the dummy grouping cause unintended page 
break after Report Header.

As in example file: 
http://user.services.openoffice.org/en/forum/download/file.php?id=5399
Two reports: Report_Header and Report_Header_with_page_header

Thanks,
Zoltan