Hi, If I left them alone they make no problems, but If I try to change the airport with ADE and I forget to examine the rwy‘s and there is no black line, AI disappeare!OK - but that is not necessarily a fault since there are plenty of runways at small airfields which don't have a runway link
In prínciple you are right but I often found stock airports with parking spots and taxiways but no black rwy-line! So I thought all is OK and I had troubles with my AI.Runway centre lines are used only by Ai aircraft. The designer is the only person who knows whether to allow AI. So he also knows to add a centre-line.
It should not be the job of the fault finder.
BTW. The same applies to hold-short nodes. The fault finder does not check whether any are missing. Nor should it.