Can't run a simulation with Nero and LTR-32123S

[CDRecorder]

With Nero 5.5.10.28 on Windows 98 (first edition), it won't let me run a simulation unless I turn off SMART-BURN. Turning off SMART-BURN limits write speed to 16x. The burner is a LTR-32123S, which has firmware XS0Z.

Interestingly, it would let me run a simulation normally on my LTR-48125W, but I replaced it with the 32123S because the computer is too slow to burn faster than 32x, and I have a faster computer that can burn at 48x. When I replaced the burner, I un-installed the version of Nero that came with the 48125W and installed Nero using the serial number that came with the 32123S.

[CDRecorder]

The burner obviously can run a simulation, because Nero CD Speed can run a simulation.

[CDRecorder]

I tried updating to Nero 5.5.10.35, and it didn't help. I had the firmware XS0Z installed, but I tried XS0F and XS0X, and those didn't help.

[Inertia]

Sometimes the simulation won't work in Nero unless "Buffer underrun protection" is disabled in the burn dialog (not SmartBurn). Try turning it off and see if you can do the simulation.

If it is greyed out, checking the Use Multiple Recorders box (if you have multiple burners) may activate the Buffer underrun protection box and allow you to disable it for the test. I said "may" because this works on Nero 5.5.10.7 but not Nero 5.5.10.35 when I tested with the same burner (LiteOn LTR-52246S).