When I attempt to create an ECATT for T-Code FMBB the NON-Header input fields for which I input data when I recorded the ECATT such as Fund, Fund Center, Functional Area are not listed in the Dynpro menu under field to create variables?
You'd better use BAPI method via LSMW for budget document creation.
Agree with Eli post.
Use BAPI: BAPI_0050_CREATE
It works ! xD