Thank you... I was unable to figure out how to flash the .axf file :S I think I took a long way around, but I used DFU File Manager to inspect the posted Secret Labs tinyclr.dfu. I used fromelf on the .axf to verify the loading address for each of the 3 boot, config and flash files. Then I used DFU File Manager again to combine the 3 bin files into a DFU. Success, I have a STM32F4 Discovery running netmf. Again, thanks for your help. Looking forward to the source patches for GCC!
I don't suppose you'd be willing to share your compiled code?