XI BPM issue

I have two source file for payment terms T052 and TVZBT . We have used BPM to merge the two files into one file containing Payment terms , text and other fields.

Now we have written a Java function which basically matches the payment terms in table T052 & TVZBT to retrieve the payment term text and if text is empty, replace it by payment term value.

Now the issue is even though the message mapping and interface mapping seems to work fine and replace the empty text with payment term but unfortunately when we do a file to file transfer through FTP , the result is not the same as the MM and IM test.

Need you expert help immediately.

Thanks,

Nivedita