In my case, same ASUS drive cannot write DVD-RW, but CD-R and DVD-R can write correctly with SB600; CD-RW has not been tested.

I installed Zelphyroth 10.5.2. Normally it would use AppleVIAATA for SB600 SATA. But it causes same problem as you; unable to write CD/DVD. I changed to AppleAHCI, then I can write CD-R and DVD-R.