Nuendo 5.5 ha a way too many issues:
1 crashes when trying to audiomixdown a project as seen below the Post.
2 Corrupts projects and they just can’t open in any other previous version
3 As we mixdown the mix isn’t correct with the project ???What happend here
4 When using a Virtual instrument which is an industry standard like East Weast Quantum Leap, 2 in q0 times it crashes
Please this is a rescue call, i have lot of work pending, and i couldn’t just deliver a mix in time which makes me in a fury.
I’m running 3 Studios and each one has a different DAW and Software, had some issues but none of this magnitude.
In the Nuendo 5.5 i’m running a MAC PRO 2.6, 8GB ram, laptop macbook 2.8Ghz 4GBram 500Gb disc, both on mac OSX 10.6.8, i use also Metric Halo 2882 card.
Process: Nuendo 5.5 
Path: /Applications/Nuendo 5.5.app/Contents/MacOS/Nuendo 5.5
Version: 220.127.116.116 (18.104.22.1686)
Code Type: X86 (Native)
Parent Process: launchd 
Date/Time: 2012-01-17 15:54:13.657 +0000
OS Version: Mac OS X 10.6.8 (10K549)
Report Version: 6
Interval Since Last Report: 36343 sec
Crashes Since Last Report: 30
Per-App Interval Since Last Report: 22625 sec
Per-App Crashes Since Last Report: 16
Anonymous UUID: 47693E3F-72D0-46FA-895A-3E5AB04AF1D2
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x000000005696a000
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
[crash log deleted - is of no use for the users - Fredo ]