I think it's not possible. Connect in online mode without source code (to see program in STL) or convert VxWorks-similar instructions -> STL code - definitely not.
Maximum what you can do - make binary dump of existing program.
Anyhow, try read Section 6: The SD memory card in the AC500 in this document: https://rapidshare.com/files/2874553117 ... 0M0203.ZIP
maybe you'll find something useful.