I would also like to know how this was resolved. I recently upgraded a 650 from 6.1. to 6.3.1.6, and am unable to convert RAP3WNP's up to it. Sits at the downloading controller information screen for 15+ minutes before it looks like it gives up and reboots. After a 2nd attempt on the 2nd RAP3WNP it failed, and on the RAP3 it said "Retrieve image failed, please save the log in the popup window."
Tried this on multiple RAP3's without sucess. RAP2's and RAP5's that were already configured in 6.1 are all working fine.
Already have a TAC case, will post back when my issue is resolved.