AGS Checker - error AGS4 checker

Hi

When trying to output an AGS4 file, I get the following error from the AGS checker. 

Error in  CheckFileFailedFnB: Type Mismatch

This is from a slightly modified correspondence file based on the Bentley AGS4 Template.

The output report contains:

Size:  10,018 bytes
Number of Lines:  153

SUMMARY:  No problems found in file.
Could not continue with further checking.

Could someone explain further how the AGS output command works? For instance, the AGS file contains ABBR, TYPE and UNIT groups - all set as <<OMIT>> in the correspondence file. The AGS file doesn't contain a DICT group, although the correspondence file suggests it should:

DICT,DICT
DICT_TYPE,<<DICT.DICT_TYPE>>
DICT_GRP,<<DICT.ItemKey>>
DICT_HDNG,
DICT_STAT,
DICT_DTYP,
DICT_DESC,
DICT_UNIT,
DICT_EXMP,
DICT_PGRP,
DICT_REM,
FILE_FSET,

...

Thanks for any help.

Tom