I see what you mean about the latest FCO map (below) which shows a red band along the horizontal border with WS.
The question is: does that band cover the railway and adjacent piste to the south of it?
Or does it just refer to the area north of the rails which has always carried small risks (landmines)?
I would interpret it as the latter, otherwise the band would be much broader to eliminate any ambiguity and it would not reach right to the coast including the highway out of NDB. This exposes the arbitrary nature of the FCO zoning, even though they are much much better than they used to be. The French 'FCO' currently have a
mildly less severe map. Important to remember it is travel
advice, not an edict, and they of course err to the side of caution.
I have not driven this route for many years but have read here that the track has become much better formed than it was in my day (not that orientation was ever difficult) and that checkpoints exist now.
Depending on when you arrive, these checkpoints may try and insist you overnight there, but I would guess that is only because that's what they've been told to do with foreigners, rather than any real threat from banditry.
Of course my opinions are only based on information anyone can read, but there is also long experience in interpreting where real dangers might be. The short version is: if the area is off limits the police won't let you pass.
Assuming you are travelling alone, it can be intimidating setting off along a long desert piste (as I mentioned to someone else recently) - even a technically easy one like this. The best thing would be to eye up a possible companion in another vehicle as you head south towards NDB (or off this forum). Even just a bike. Everything feels less daunting when there's someone else around to hold back the paranoia. Such temporary travel arrangements are common in the desert and part of the fun.
Then, when you get to Atar (no need to go via Choum), you will think that wasn't so hard - bring it on!
(It's hard to think why the FCO have put Chinguetti in the red zone, but if it's so risky you will be stopped from leaving Atar on the single main track that goes there.)
I say all this because a lot of people shoot through Mauritania and so the Sahara and miss one of the best aspects of the drive to West Africa. You will not forget the couple of nights you might spend on the piste in the desert.
Ch