I feel like I should know this already but the rule about South Africa / Mauritius, I find confusing.
TRAVEL TO/FROM/VIA AFRICA. IF TRAVEL IS TO/FROM EUROPE IN BOTH DIRECTIONS ITINERARY MAY NOT INCLUDE MAURITIUS/SOUTH AFRICA.
I think this would clearly preclude you from using BA both directions, but what about QR? It does say Europe, and does not mention the Middle East, even though the Middle East is treated as Europe for most purposes. Or does this require you to either enter or depart South Africa on CX or QF (I think those are the only non-European / Middle Eastern OW airlines flying there)
Second question, and I think the answer to this is yes, since there are no longer any OW carriers in Africa (not counting AT here since that's still a zone considered Europe), can you, for example, go xxx-LAX-DOH-NBO-DOH-ACC-DOH-yyy-zzz-xxx ? Or is it now impossible to have more than one Africa destination (excluding ground segments) on a DONEx?