I use Editor 1.7.4 and RowReorder 1.2.4 , when i drag the row and change the position, and i don't see any ajax post request or error in console, i found the bug code is
var id = dt.row( endNodes[i] ).id(); // get undefined
var endRowData = dt.row( endNodes[i] ).data();
var startRowData = dt.row( startNodes[i] ).data();
so i change the code as follow, and it works
var endRowData = dt.row( endNodes[i] ).data();
var id = endRowData.id; // get row id
var startRowData = dt.row( startNodes[i] ).data();