Place the file in a 'corporate' WDIR, one everybody has read-only access to and leave the 'user' WDIR for each engineers personal settings. The WDIR would look something like:
Where CorpWDIR is readonly.
Reference the Concurrent Design Administrator's Guide shipped with the documentation set if you have it, it covers setting things up read-only so users cannot change them inadvertently.
WHERE IS THE XML FILE THAT IS USED LOCATED.
Two places - the corporate WDIR first and then if a user changes anything it gets written to the user's WDIR and overrides the setting in the corporate WDIR - read the manual.
Look in the help documents, xDX Designer and xSD Systems Designer Administrator's Guide.
DxDesigner.xml File Precedence Order
On supportnet, this is my link