For posterity’s sake I will add my experiences I endured today for the betterment of anyone going thru the same thing in the future, at least as far as MacOS is concerned.
The Cubase SX 3.1 download will only work for those with the full Cubase license. For those who need to convert songs from Cubase VST into Cubase Artist they will need to download Cubase SL 3.1 as (almost) explained in this post
http://www.steinberg.net/forum/viewtopic.php?f=20&t=230
I say almost as I missed this point the first time I read it and not until it was pointed out to me by another member did I understand the correlation.
Also there is a bit of a song and a dance to go through in regards to the eLicenser, at least for me it was. I had to uninstall the eLCC app from my system, and go to http://www.elicenser.net/en/download_archives.html and download an earlier version (6.0.4 in my case). Once that was installed, I installed SL3.1 (making sure the USB dongle was not plugged in).
I was then able to launch Cubase SL and then I could reinstall the most up to date version of eLCC. Not sure why this was the case, but Cubase SL was looking for some particular libraries that must have been named differently in earlier eLCC versions. Go figure.
The final step as was suggested here was to move all plug-ins out of the /Library/Audio/PlugIns/VST folder into a **Disabled folder I created. Otherwise Cubase SL did indeed crash.
It took me all day installing and uninstalling various versions of software to finally get to a solution that worked for me. But I’m really happy to ay that I was able to import the Cubase Song and Arrangements and save them out as .cpr files flawlessly. There are a number of VST effects that were missing due to renaming (chopper2, metalizer2) and not being installed (Waves, GRM) but I have a workflow to get around that. Fortunately SL is able to export a text file of all instances of missing VSTs to make it easier to keep track of.
Finally there was a lot of finding of missing audio files, but that was pretty flawless, just time consuming. When that was all done everything was in order (except for the missing plug ins).
Thanks for all the expert help that got me through this today. Hope these additional notes help somebody else in the future.
To get my tracks back to where they were in VST5 I created the following workflow. It’s a bit convoluted, as I could not get the Save Preset .fxb to work from one platform to the other. That would be ideal. However I had to go through every track in VST5 and open its track window, and opening the edit window for any insert effects I had. With these windows open I took a screen grab, for each and every track in the mixer, and the same for any send effects used. With this database of reference images and the missing plug-in text files I can go back and recreate the effects structure of my song.
Good times