Firmware upgrades and resuming Multi-session burning

I have a Gigabyte GO-W1608A drive which is a rebadged 1633S. I’ve corssflashed it to a 1653S.

I had this problem in two firmware upgrades. Can’[t remember the first one.
I had a DVD which was started as multi-session disc before upgrading to CS0M and it was started when the drive had CS0K firmware version. After upgrading to the latest, I burned another session to it, but the new session is not shown in the drive. And it is finalized, although I specified it not to.

More info:
Disc: TDK distributed CMC MAGE01
Software: Nero on WindowsXP SP2
Curent firmware = CS0M with 16X r/s mod and LED fix crossflash enabled
Previous firmware: CS0K with 12X r/s mod and LED fix crossflash enabled

What is your opinion? Is there a problem with the drive?