Bug 183900 Image in preview pane will not show until you reopen the "Edit Image Item" dialogue [0001]
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ImageBuilder.java
if ( DesignChoiceConstants.IMAGE_REF_TYPE_EMBED.equals( inputImage.getSource( ) ) )
		{
			String imageName = inputImage.getImageName( );
			if ( imageName != null )
			{
				index = embeddedImageList.indexOf( imageName );
			}
		}
		if ( index != -1 )
		{
			embeddedImageList.select( index );
			preview( );
		}
		else
		{
			clearPreview( );
		}
		updateButtons( );
	}
	private void updateButtons( )
	{
		boolean complete = false;
		switch ( selectedType )
		{
			case BLOB_TYPE :
				complete = !StringUtil.isBlank( uriEditor.getText( ) );
				break;
			case URI_TYPE :
				complete = !StringUtil.isBlank( uriEditor.getText( ) );
				break;