Good afternoon

I have a couple of questions please.

I see in the wiki and the rules that: Generally, the ticket will be issued by whichever airline flies your first segment.
1.Does this mean that if i call BA cause the 1st flight might be with them, all flights will receive a BA codeshare number or each flight will have its primary flight numbers as oneworld's rtw site?
2. Has anyone used BA to make a rtw ticket a BA holiday or it's not possible?

Thanks!