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
case EMBEDDED_TYPE :
				complete = ( embeddedImageList.getSelectionIndex( ) != -1 );
				break;
			case FILE_TYPE :
				complete = !StringUtil.isBlank( uriEditor.getText( ) );
				break;
		}
		getOkButton( ).setEnabled( complete );
	}
	private void openExpression( )
	{
		ExpressionBuilder expressionBuilder = new ExpressionBuilder( uriEditor.getText( ) );
		unionDataSets( );
		expressionBuilder.setExpressionProvier( new ExpressionProvider( inputImage ) );
		if ( expressionBuilder.open( ) == OK )
		{
			String uri = expressionBuilder.getResult( );
			uriEditor.setText( uri );
			preview( DEUtil.RemoveQuote( uri ) );
		}
	}
	private void openBidingDialog( )
	{
		ReportItemHandle handle = (ReportItemHandle) inputImage;
		ColumnBindingDialog dialog = new ColumnBindingDialog( PlatformUI.getWorkbench( )
				.getDisplay( )
				.getActiveShell( ),
				true );
		dialog.setInput( handle );
		if ( dialog.open( ) == Dialog.OK )