The only really supported version of NeroSDK was with
Nero 6. Since the launch of Nero 7 this board has been abandoned by Nero/Ahead, basically we are now on our own - and it is my experience that bugs are creeping into the SDK which since the developers have abandoned this board are not being resolved.
In short the last versions of Nero 6 work well with the SDK, I have found 7 works with some workarounds. I haven't daren't try 8 yet but I don't expect it will be an improvement on the SDK front - your experience seems to confirm this!
There are freeware alternatives out there which have a released API - I intend to investigate these.