Please check John's blog: http://john-goodwin.blogspot.com/2008/08/time-to-look-in-bin.html
This is how I learned to use the OLU.
I'd also check the admin guide.
To load data: http://download.oracle.com/docs/cd/E17236_01/epm.1112/hp_admin/ch05s02s01.html
To load metadata: http://download.oracle.com/docs/cd/E17236_01/epm.1112/hp_admin/ch05s02s02.html
I have loaded Dimension members in Planning Application using Outline Load utility...All the members got loaded but are applicatireflecting the same in the other ons too....I checked the Datasource is also different for different Applications. Please guide as to what could be the coz of the error...