Hi Ralf,

We will make headerMap and map compatible with each other in the next release of Pivot. For the time being, you could fix this issue by opening the file Pivot/PivotUtil.php and replace these lines:

        list($mappedFields, $rowFieldsClass, $rowFieldsExcelStyle) = 
            $this->getMappedFieldsAttributes('row', $rowFields);
        if (! empty($this->map)) $mappedRowFields = $mappedFields;
        list($mappedFields, $colFieldsClass, $colFieldsExcelStyle) = 
            $this->getMappedFieldsAttributes('column', $colFields);
        if (! empty($this->map)) $mappedColFields = $mappedFields;
        list($mappedFields, $dataFieldsClass, $dataFieldsExcelStyle) = 
            $this->getMappedFieldsAttributes('data', $dataFields);
        if (! empty($this->map)) $mappedDataFields = $mappedFields;
        list($mappedFields, $dataHeadersClass, $dataHeadersExcelStyle) = 
            $this->getMappedFieldsAttributes('dataHeader', $dataFields);
        if (! empty($this->map)) $mappedDataHeaders = $mappedFields;
        list($mappedFields, $waitingFieldsClass, $waitingFieldsExcelStyle) = 
            $this->getMappedFieldsAttributes('waiting', $waitingFields);
        if (! empty($this->map)) $mappedWaitingFields = $mappedFields;

        list($mappedNodes, $rowNodesClass, $rowNodesExcelStyle) = 
            $this->getNodesAttributes('row', $rowNodes, $rowNodesInfo);
        if (! empty($this->map)) $mappedRowNodes = $mappedNodes;
        list($mappedNodes, $rowNodesClassBun, $rowNodesExcelStyleBun) = 
            $this->getNodesAttributes('row', $rowNodes, $rowNodesInfoBun);
        if (! empty($this->map)) $mappedRowNodesBun = $mappedNodes;
        list($mappedNodes, $colNodesClass, $colNodesExcelStyle) = 
            $this->getNodesAttributes('column', $colNodes, $colNodesInfo);
        if (! empty($this->map)) $mappedColNodes = $mappedNodes;

with these:

        list($mappedFields, $rowFieldsClass, $rowFieldsExcelStyle) = 
            $this->getMappedFieldsAttributes('row', $rowFields);
        if (isset($this->map['rowField'])) $mappedRowFields = $mappedFields;
        list($mappedFields, $colFieldsClass, $colFieldsExcelStyle) = 
            $this->getMappedFieldsAttributes('column', $colFields);
        if (isset($this->map['columnField'])) $mappedColFields = $mappedFields;
        list($mappedFields, $dataFieldsClass, $dataFieldsExcelStyle) = 
            $this->getMappedFieldsAttributes('data', $dataFields);
        if (isset($this->map['dataField'])) $mappedDataFields = $mappedFields;
        list($mappedFields, $waitingFieldsClass, $waitingFieldsExcelStyle) = 
            $this->getMappedFieldsAttributes('waiting', $waitingFields);
        if (isset($this->map['waitingField'])) $mappedWaitingFields = $mappedFields;
        list($mappedFields, $dataHeadersClass, $dataHeadersExcelStyle) = 
            $this->getMappedFieldsAttributes('dataHeader', $dataFields);
        if (isset($this->map['dataHeader'])) $mappedDataHeaders = $mappedFields;

        list($mappedNodes, $rowNodesClass, $rowNodesExcelStyle) = 
            $this->getNodesAttributes('row', $rowNodes, $rowNodesInfo);
        if (isset($this->map['rowHeader'])) $mappedRowNodes = $mappedNodes;
        list($mappedNodes, $rowNodesClassBun, $rowNodesExcelStyleBun) = 
            $this->getNodesAttributes('row', $rowNodes, $rowNodesInfoBun);
        if (isset($this->map['rowHeader'])) $mappedRowNodesBun = $mappedNodes;
        list($mappedNodes, $colNodesClass, $colNodesExcelStyle) = 
            $this->getNodesAttributes('column', $colNodes, $colNodesInfo);
        if (isset($this->map['columnHeader'])) $mappedColNodes = $mappedNodes;

Let me know if this works for you. Thanks!