i asked him real quick about it, and he said he stripped out about 100lines of code....
if your going to play around with the port1_config_descriptor, forget about using it in descriptor.h, he is calling for it in port1_config_descriptor.h in more then one location. just use that file to reflect what you want to do.
again, make -f Makefile.payload is the command to get the .h file.
i took the liberty of copying your payload from descriptor.h and put it into the port1_config_descriptor.h and compiled and the payload is no longer successful. the ps3 boots, but it does not boot into debug (no install package,etc).
ok this payload has been edited to hopefully have the bdvd enabled. I took a different root then messing with payload_apploader.S so hopefully it will work. if it does not then I will look into payload_apploader.S with you but I think that the payload I have in port1_config_descriptor.h will be needed no matter what to enable bdvd.
As for payload_apploader.S it is a modified payload_default.S with only code added for usb support.