Since the new DML 2.0 API is now in place, all code using the old dmllib needs to be upgraded. In essence, this means the following changes:

1. Wherever old functions are used (get_record*, get_field*, set_field, insert_record, update_record), the global $DB must be used as the object on which these functions are called (e.g. get_record_select becomes $DB->get_record_select).
2. All the functions that used to accept a list of string params in the form "param1, value1, param2, value2" now need to be given an array of key=>value pairs as a replacement for these params. Other params remain as before. Check the new API for any exceptions.
3. rs_fetch_next_record($rs) is deprecated, in favour of the simple foreach($rs as $var). Calls to rs_close() must be replaced by $rs->close();

As an example to #3, if you have the original code:

     while($result = rs_fetch_next_record($rs)) {
         ...
     }
     rs_close();

you would replace it with

     foreach ($rs as $result) {
          ....
     }
     $rs->close();