>>>Is the network slow when your application is *not* running?
>Apparently not.
>
>>>Is the application running on any other similar sized networks without problems?
>Unfortunately this is currently the only installation of this application.

How big are the tables ?
I'd check that all queries are Rushmore optimised (or should not be) - see the 'Rushmore' section in this from Christof:
http://www.foxpert.com/docs/howfoxproworks.en.htm
Also take his advice re: using NetMon or similar to find out exactly which files (or parts of files) are being sent to the workstation (you can test that yourself on any setup where the DBC is on a different machine to the EXE)