The following FAQ provided by David Alford:
How does BCA save files?
Save As without directory. By default BCA will save to …Program Files\Business Objects\BusinessObjects 5.0\UserDocs. When you save a file you have to use a fully qualified UNC (\servername\directorypath). The user that starts Business Objects on the server must have rights to write to the specified directory.
UNIX will default to saving in /WIData/UserDocs. At one time AIX could not save to any other directory. Not sure if that is fixed yet or not (we switched platforms from AIX to W2K)
Nick Daniels 
(BOB member since 2002-08-15)