Resolved.
HDR and LINE fields in the import file must denote what data is header and what data is line information.
Example of .csv type import
HDR,date,description,check amount,LINE,account no,amount
HDR,date,description,check amount,LINE,account no,amount
HDR,date,description,check amount,LINE,account no,amount
Remember that one cannot leave a blank line behind the last line in the import file - will continue to run without doing anything (need to terminate the application).
Cheers,
Benjamin