To fill CATSDB (as you could find in the previous link posted) use BAPI like BAPI_CATIMESHEETMGR_INSERT, BAPI_CATIMESHEETMGR_CHANGE and BAPI_CATIMESHEETMGR_DELETE. You can also read data from catsdb and convert it using MAP2E_CATSDB_EXT_TO_BAPICATS2.
For simple Attendance data, you may not actually require time sheet but time infotype 2011 and interface like BAPI_CC1_UPLOAD_TIMEEVENT.
That can be easily found via transaction BAPI or searching scn. What is theissue thatis causing you problems?
Regards,
Raymond