Is it possible to use a temp table in a data flow source?
These steps helped me:


Write the final result set into a table.
Script that table as CREATE into a new New Query Editor Window.
Remove everything except the open and close brackets that define the columns.
Wrap that into another pair of brackets.
Recompose the calling of your SP from

exec p_MySPWithTempTables ?, ?



into

exec p_MySPWithTempTables ?, ? with result sets
(
    (
        ColumnA int,
        ColumnB varchar(10),
        ColumnC datetime
    )
)