avoid error when number of columns in table definition has been increased

composer/schema/grid/field.py

@@ -242,6 +242,7 @@ class KeyTableFieldInstance(RecordsFieldInstance):
         for k, v in value.items():
             row = [k]
             for idx, fi in enumerate(self.columnFieldInstances[1:]):
+                if idx < len(v):
                     row.append(fi.display(v[idx]))
             rows.append(row)
         return dict(headers=headers, rows=rows)