The yellow sports car taken by Abby appears to be a 2008 Lotus Elise.
At about 41 minutes the camera takes the POV (point of view) of a first person shooter video game.
Whilst Cutter is correct in contacting the Highways Agency (now Highways England), the control rooms are incapable of using free text on the motorway message signs. This capacity was removed whilst the signs were still set by police due to non authorised messages having been set in the past.
Ben Miller (James Lester), Hannah Spearritt (Abby Maitland) & James Murray (Stephen Hart) all appeared on episode 2.6, A Dash of Sunshine (2013) of Death in Paradise (2011) as DI Richard Poole, Lily Shaw & Ronnie Stuart respectively.