function getProps(op) {
      var verb = op[0],
          options = op[2] || {};

      var props = ['opacity'];
      if (verb == 'animate') {
        props = [];
        for (i in options) {
          if (i == 'style') {
            for (j in options.style) {
              props.push(j);
            }
          }
          else {
            props.push(i);
          }
        }
      }
//      log('getProps', op, props);
      return props;
    }
Correct reversed delays by measuring total track length and adding the missing final / reversed initial delay.