This has been an issue for me for some time. I work at a high school and manage 500+ computers with Workgroup Manager. WGM is used to lock access to applications and other parts of the OS. There is an option, just like with the parental controls, to allow access to applications not on the list of approved applications if another application needs them.
One example outside of MS Applications is when you click on an iTunes music store link it will open iTunes. We do not want the students to access iTunes because there home folder is store on a server and it is disruptive.
With WGM you have the power to allow applications or deny applications. If an application is denied it will not open from another program if it is requested. Since Parental Controls doesn't deny access to the application it just isn't allowing to be directly opened it opens.
One thing you can do is allow the supporting programs one at a time using the locate option and uncheck the option to allow supporting applications. It is a pain when it comes to MS Office. There are quite a few supporting applications for MS Office.
Another option is to place the applications you want to deny in a separate application folder that does not have read or write access for the managed user.
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