You did remove the
On-Star (Info) fuse under the hood before starting to program, right ?
Did you try to follow the programmers instruction on recovering from a programmer hang up by leaving the key on and disconnecting the programmer, may have taken a couple times to work.
You might have to send the programmer and vehicle computer in to them now according to a couple sentences out of their manual
Do Not Turn The Ignition Key Off
1. Disconnect the programmer from the vehicle.
2. Reconnect the programmer to the vehicle.
3. Press the START button on the programmer.
The programmer will resume communications with the vehicle
where it left off. If the programmer fails to re-establish communications
with the vehicle, repeat the procedure. If the programmer
still fails to resume, disconnect the programmer and turn the
vehicle off. Attempt to start your vehicle. If your vehicle fails to
start, the vehicle computer may have been corrupted, and you
will need to send your vehicle computer and programmer to
Hypertech for repair. If the vehicle starts, you will need to return
your programmer to Hypertech for re-initialization, no harm was
done to the vehicle computer.
Sorry for the possible bad news, Ed