Don’t know why you are having this issue … but I run studios and labs with hundreds of (non-admin) users … the set up seems a bit fiddly when written down but it’s easy once you’ve done it. There’s 2 steps
1: make a non admin account that works, and you want all users to start with
2: replace Apple’s default account template with this.
From your main Admin account create an account which will be the template for all other users. The ideal time to create it is after the OS is installed and fully updated. So, do that, then create a new account. Initially this will be admin level, but we’ll change it later. I call this user, “usertemplate” Log out of your Admin account.
Then log in as “usertemplate”. I configure preferences, Dock, Desktop etc as I want it to be for each user when they first log in. Then I install all apps … Nuendo included. Install plug ins and enter serial numbers. Test it with your audio I/O and make it work as you want. If possible large content folders belonging to plug ins or instruments (sample libraries, video etc) should be directed to another folder on the outside of the account. You could create a folder at the root of MacHD, called "Program Content for instance. Otherwise each user will get a complete copy of all content libraries!
Then, for a nice clean template account:
Open Safari and reset it.
Empty the trash.
Do a spotlight search for “key” and open the Keychain Access app. There is an entry on the left which says LogIn. Select it, hit “Delete” on the keyboard and select All Files and References. This will stop the OS asking for new keychain passwords when users log in later.
We are now going to enable the root user for the machine. Root user is simply an account called “root” (ie username= ‘root’) that lets you do anything to the OS and all it’s files and components. No holds barred.
Go to the System Preferences / Accounts pane. Click on the Usertemplate account, click Log In Options, click on “Join Network Account Server” (don’t worry you’re not actually going to do this!) and click on the button at the bottom called “Open Directory Utility”. It runs an App called Open Directory Utility … go to it’s Edit menu (at the top of the Finder) and click on Enable Root User. You will set a password.
Quit Open Directory Utility.
Finally Click on the usertemplate account and deselect "allow user to administer computer’.
Your usertemplate account is now non-admin and ready to be used as the template for everyone. It has all its serial numbers, authentications, shortcuts, app preferences etc all ready to go.
OK log out of usertemplate. Log in as “root”. You are now in total control and we want to replace the template Apple uses to generate accounts, with our usertemplate account.
So, for safety lets copy the Apple account: its called “English.lproj”
Navigate to MacHD/System/Library/User Templates (note: you can’t get into this unless you are logged in as root!)
In this folder you’ll see a folder called “English.lproj” alt/Drag it onto your desktop as a backup.
Now go to MacHD/Users. In there you’ll see the Account folder we made called “usertemplate”. alt/drag it to the Users folder. This will create a copy of it called “usertemplate1”. Click on it a rename it “English.lproj”.
Drag this “English.lproj” in to the MacHD/System/Library/User Templates folder. Let the OS replace the old one (which we backed up).
Log out of root.
Now whenever you create a new user it will look and behave just like the usertemplate folder, but with the name/password set up for the use. Nuendo runs fine like this.
Caveat: some plug ins/ Vsti’s and even apps don’t like (or even licence) multi users on the same machine. Some need to be installed in the MacHD/users/Shared folder. Some need the permissions on their preferences/ Application Support/ or even Application folders set so all can read/write. If you experience any anomalies you just re-log in to the original “usertemplate” account, adjust things, recopy it, rename it English.lproj, and replace the one giving trouble (as root user of course). If that doesn’t work hassle the developers!
If disaster strikes you always have the original Apple Template copy on the root/Desktop to put back in place.
I’ve been doing this since OS10.0. and it works great. There are faster ways of doing all this with the Terminal/Automater etc … but dragging and dropping is easy and undoable!
Hope this helps