After receiving a 3rd liteon to fix with the same problem, I think an extra measure is needed when flashing these drives.
You should now remove the laser ribbon from the laser head.
The reason for this is that it appears that some lasers will be bricked during the flash process.

If you have flashed a liteon & it is displaying the open tray error,1st try adding a memorycard or HDD to the system.
If you still have the error you will need to buy a replacement benq laser.
The benq laser is compatible with the liteon drive.
Before you install the laser there is an anti-static solderball that must be removed.