[Unattended Install Programs?]

Try to modify your winnt.sif according to:

http://unattended.msfn.org/global/reference.htm

Try 'AutoPartition' and/or 'Repartition'

Also make sure your 'ProductKey' is correct

[Nero Burning ROM v7 installation]

Try to first import registry of serial. After the installation it's located in:

HKEY_LOCAL_MACHINE\SOFTWARE\ahead\Installation\Families\Nero 7\Info

And then run:

Nero.msi STARTPARAM="CallFromExe" DONOTRUNSETUPX="1" /QB REBOOT=ReallySuppress

[Nero Burning ROM v7 installation]

I just import the registry file and then run the installation with no switch after changing the SFX script using WinRAR:

;The comment below contains SFX script commands

Setup=Nero.msi STARTPARAM="CallFromExe" DONOTRUNSETUPX="1" ADDLOCAL=ALL /QB REBOOT=ReallySuppress 
Path=%temp%\Nero7.tmp
Silent=1
Overwrite=1
Title=Nero 7.0.1.2 - Nero AG