Welcome to Flyer Talk Glycerol

Do you have problems with security with a name like that?

NAN is not served by oneworld and would require either a separate ticket, or use of the global explorer RTW (instead of oneworld explorer).

But your itinerary is rather long and global explorer is mileage based, thus you'd need to drop some segments.

RTW tickets allow 16 flights. You will need to either drop some (or buy extra tickets for side trips) because you cannot fly your draft itinerary in only 16 flights. Most of your stopovers have no direct oneworld flights in between.

There is no intra-Africa flights on oneworld between NBO and JNB (NBO to JNB via LHR is not allowed because it is backtracking between continents). Thus this would need to be a surface sector (ie buy your own ticket) and surface sectors still count towards the maximum of 16 "flights".