As mentioned earlier all aircraft should be following the ICAO format for there Flight IDs. There is no issue with our software, it was designed to handled what is specified which in this case is ICAO format flight ids.
As a famous programming saying goes, garbage in -> garbage out.
In the past when we have seen non ICAO codes they usually been mistakes and eventually been rectified. When the next version is released, if there is a significant portion of non ICAO flights appearing we may change the system to allow these routes.