Howdy,
We entered Ghana today -- on the insistence of Cote d'Ivoire gendarmes in Yakasse (east, north of Abengourou) -- they suggested the military is fighting bandits on all roads going north. We were planning to visit Comoe' park, but we verified the story with a local policeman, the drug enforcement, and a military dude. Frankly, our french isn't so amazing that we could ask people confidently, but they were all insistent that there was some sort of problem.
That said, we have done the reverse of your route, generally (see my sig), and we have had ZERO problems. Guinea was a breeze (a painfully rough road between N'zo and Danane, but if we can do it in a Subaru, anyone can do it), and we did the Mamou -> N'zerekore route and found no problems OTHER than a fuel shortage in Faranah due to the construction work on 2 of their 4 petrol stations plus a flipped tanker truck. Bring extra, they seem to be out of essence AND diesel, and show no signs of finishing their work for a month or two.
I can't speak to the Casamance region, nor Gambia, since we didn't do those -- nor Liberia/Sierra Leone.
The parts we HAVE done, however, have been super wonderful. Eastern Cote seems a little less professional, regarding stops and attempts at bribes. Guinea we only had a single incident in dozens of checkpoints over a week. Senegal didn't give us a single attempt. Mauritania gave us one or two, plus the borders are nonsenes. Morocco only had one incident, asking us for whiskey.
Tame stuff. I've been profoundly disappointed with the governmental travel info from US/UK/CA/Aus on West Africa so far, and frankly, we're sort of mad that we re-routed on the demands on the gendarmes, since we are now skipping Burkina/Benin/Togo and entering Ghana a month early -- but we have a standing "better safe than sorry" rule, so I'm curious what they're even on about. They even said the road to Bouake was no good, so either there is something flaring up, or we got trolled hard by the officials in eastern Cote.
$0.02 -- Hope it helps.
- Mike
(African newb + chicken)