Hi Stefan,

With Table or DataTables widget there's no universal way to set a metadata property across all columns but you could do that in the setup file with the Map process:

//MyReport.php
->pipe(new \koolreport\core\Map(array(
    "{meta}" => function($meta) {
        foreach ($meta["columns"] as $colName => $colMeta) {
            $meta["columns"][$colName]["thousandSeparator"] = ".";
            $meta["columns"][$colName]["decimalPoint"] = ",";
        }
        return $meta;
    }
)))
->pipe($this->dataStore("myDataStore1");

Let us know if this solves the issue for you. Thanks!