1. Model number of DVD drive - dg-16d4s
2. Original firmware version of DVD drive - 0225
3. Method of hack (Unlocked PCB / Pro Kit / Russian Hack) - Pro Kit
4. Version of fw flashed - LT+1.9
5. Dashboard version - 13599
6. Exact error (Open tray or Play DVD) - Open Tray
7. Troubleshoot tip test - working yes/no - Not sure, I no longer have the drive... but... what worked was restarting the xbox, inserting an original game first, then ejecting and inserting the backup. If the backup was put in first the xbox would display Open Tray.
I've modded several others with the Pro Kit and they work perfectly. Unfortunately, they were for customers, so I no longer have them... they were all 0225 however.
edit: I have 2 more to do today, so I'll take note of any similar problems.