Single Project Node set on Server to be shared by multiple stand-alone Users simultaneously is not f

I have a project that was exported from our Enterprise and saved as an xer on our local server.  Due to our remote location, Citrix configuration is quite slow.  It would be best to load the exported file on our local server to be used by 7 P6 schedulers.  The schedulers have stand alone versions of P6 Release 7.  The objective of this effort is to have the project file opened and shared by each scheduler simultaneously, as experienced under the Enterprise system version.

All that I have been able to accomplish is having a User import the file, complete any updates, the export the file to the server for another User to access.