Have you gone into zeroedit yet?
Go into the assets folder and copy the MSH, ODF, and TGAs for the things you want in your map. e.g. BF2MODTOOLS/Assets/Worlds/COR/(MSH or ODF)
Put them in your worlds MSH and ODF folder. e.g.BF2ModTools/data_ABC/Worlds/ABC/(MSH or ODF)
Go into ZeroEdit, object tab on the left there is a text box click "browse" next to it and go to where you put the objects. click open then the "place" button and put Objects where desired.
Save ZeroEdit
Go to data_(yourmap)/_BUILD/Modtolls VisualMunge, Munge your level and your done!
For further help check the documentation 1st.
EDIT: Oh great! I type instructions and someone else beat me to it.
