I'm trying to book the following DONE4 ticket:

WDH-JNB Comair
JNB-LHR BA
LHR-BOS BA
BOS-ORD AA
ORD-LAX AA
LAX-SYD QF
SYD-JNB QF
JNB-WDH Comair

1. My agent says that you can only do a DONE4 from JNB and that I'll have to purchase a separate WDH-JNB-WDH ticket, even though it is served by a Comair (British Air Franchise). Yet, elsewhere on this forum, it states that you can use Comair in RTW tickets? Can any one point me toward the rule?

2. The BOS-ORD and ORD-LAX are served in two class segments. Some of you on this forum state that with a DONE4, you can fly in the "first" class of the AA flight on the domestic routes, when there is no business. She insists, she can only book me in economy on the two cabin AA flights. Can you point me toward the rule?

3. I'm a BA EC member. Can I use points to upgrade the QF LAX-SYD from Business to First using a DONE4 ticket? Can you point me toward the rule?

thanks for all your expertise