Wavelab 6 won´t burn in spite of WNASPI

Problem:
CD Writer (worked under Windows xp SP3 ), won´t burn after Windows 7 64 new installation in Wavelab 6.1.1.
Writer gets recognized, seems to start writing, but finalizes all at once (after 4-5 seconds) without having actually written.
Driver WaveLabAspi (WnASPI32.dll) is installed. Nevertheless it does not work.
What am I missing?

Folks …please, thanks!

DAW:
PC I5
16 GB RAM
W7 Pro 64
WL 6.1.1
Cubase 5.5.3
CD Plextor PX 880SA

Have you looked through this?:
http://www.steinberg.net/forums/viewtopic.php?f=145&t=205

Or, generally it’s suggested to install the followng gear software for cd/dvd problems with Wavelab 8, but don’t know if that has any effect on Wavelab 6. I would create a restore point or system backup before installing this:

http://www.gearsoftware.com/support/drivers.php