Hi Robert,
Hope you've had a good holiday

I had another look at your tool - it's getting much better

I tried it with the sequence of hops that alerted me to the incompatibility of ICAO codes between FS9 and FSX (I generate hop lists in FS9 and then check they work in FSX - normally if an FS9 code isn't in FSX then I just change the destination to somewhere else in the vicinity where the ICAO code is common between FS9 and FSX). However, for FWLI in FS9 there are no other airports for hundreds of miles around that share the same code

So, the sequence is: FVHA, FLLS, FWLI, FMMI (these are three hops that are part of my "World Tour").
Your generator produced:
FVHA = Click "Create a Flight" (or use the World menu) to start at FVHA, [Harare International - Zimbabwe], located at 4902ft [1494m] (Runway: HARD) then type "?hop" for first hop instructions.
FLLS = Fly heading 315 for 218nm and land at FLLS, [Lusaka International - Zambia], located at 3780ft [1152m] (Runway: HARD), then type "?hop".
FWLI = Fly heading 74 for 323nm and land at FWLI, [ - ], located at 4035ft [1230m] (Runway: HARD), then type "?hop". NOTE: FSX pilots fly to FWKI and then type "?hop".
FMMI = Fly heading 112 for 844nm and land at FMMI, [Antananarivo Ivato International - Madagascar], located at 4199ft [1280m] (Runway: HARD), then type "?hop".
which is pretty good.
In fact, it seems that I made a mistake in my hop list instructions for the FSX part of FLLS to FWLI - I should have used FWKI

I will go and correct that now.