Just saw this thread as well.
Few things. Instead of wasting DVDs to burn and see if it works....
When you successfully create a DVD-A in Wavelab, it renders the files into the AUDIO_TS folder. You can then use WinDVD 6 to open files/folders from your hard drive. WinDVD 6 supports playing of DVD-A, btw.
The other method is using the above said program (Audio DVD Creator?) and write the disc image to the harddrive and use a program called Daemon Tools that mounts a CD/DVD image and makes it show up as a new drive on your computer. Then follow the open from hard drive approach in WinDVD and point to the newly mounted drive (point it to open the VIDEO_TS folder instead)
This is a good way to test and make sure everyting is kosher before actually burning the discs. At least this is what I do/did.
Hope this helps!
Martin