My Dears,
After some bad experience with plain broadcast wave files
(Long Recording makes unreadable file - Nuendo - Steinberg Forums - unsolved 
)
I tried the w64 extension for my “all night long 24-96 surround recording”. Twelve hours of four mono channel b-format recordings, about 12GB each file (I’m not so brave to re-try a four-channel recording in a single interleaved file, I’ve lost my Muchness).
After the stop-recording all files appeared to be ok (visually, the images i mean) but with a rapid skip to check listening my creaky heart had revealed that only the first six hours was producing sounds while the last six hours doesn’t sounds both in play either in scrubbing. Only if each track is opened in the sample editor it sounds properly also in the second half.
My first attempt to solve this problem has been to find the point of silence (the same in each of four files, after about six hours), split they a little before and bounce with replace the second part of recording (without changing the format).
This works and now i can play all the session regularly.
But this has required other 6GB x 4 files and much more coffee time.
The recording machine:
MAC OS 10.8
NUENDO 5.5.4.153
MACBOOK PRO 2.66 - i7
EXTERNAL 2TB LACIE QUADRA HDD
I don’t know if this can help, but after the 5.5.4 update I had to throw the NUENDO5 Preferences Folder because NUENDO could not record anything. A lot of drop convinced me to smooth NUENDO with a new dress.
It works, maybe… an half.
Thanks.
Giuseppe.