I figured I'd post back with my experience crediting AF/KL/DL codeshare flights to AS:

Basically, after manually sending the boarding passes, AS gave credit for partner flights booked as codeshares, but subject to fare class restrictions of the operating carrier. Here's the two itineraries I've tried:

1) Open jaw transatlantic DL booking with three DL domestic legs, two AF transatlantic flights, and two AF regional flights. All were booked as DL flight numbers.
I knew when I bought it (I had to call up the DL elite line to get this info, it's not on the website) that the return AF leg was booking into U, for which AS gives no credit. I submitted the boarding passes in two separate letters. Originally, they gave full credit for the return segment in U(!). When I found and sent the outbound boarding pass, they credited it in full, but removed credit for the return, but gave back a "SPECIAL SERVICES CUSTOMER SERVICE GESTURE" for RDM only, no bonus. The DL domestic legs credited automatically.

2) Open jaw transatlantic AF booking, SEA-ATL-CDG-VRN, return AMS-SEA. Only CDG-VRN was AF metal, everything else was DL metal. Outbound flights were booked as AF numbers, return was booked as a KL number.
Nothing posted automatically, but all was credited upon manual submission.

So, credit is not guaranteed, but it does seem you have some flexibility in booking Skyteam tickets. This is a huge deal for european travel, given the present DL/AF/KL booking mess. I hope this helps some people!