The pop-up box only has the actual position of G-NMID and the altitude?
What else are you expecting to see? I get:
Date - Time
Mode S
Flight ID
Registration
Aircraft (Type)
Routing
Altitude
Speed
V/S
Heading
Sometimes I don't get speed, V/S and heading. Also, you won't get a route for this particular aircraft as it isn't an airliner. You probably won't get a Flight ID either as the pilot probably won't have set it in the Mode S box in the aircraft. I'd be surprised if you are getting a position report for this aircraft, a police helicopter.
I've checked my database and G-NMID isn't in it, so I presume that you have had the details auto-populate your database. When G-NMID appears in your MyFlights list, do you see the aircraft details then?