hi doris,
there is a way, but not with glogarchive itself. use sqlitebrowser to edit the archive: http://sourceforge.net/projects/sqlitebrowser/
1. copy the archive from your phone, to your pc. this is the file: /home/user/.rtcom-eventlogger/el_archive-v1.db
2. make a backup of the file
3. open the file with sqlitebrowser
4. there you can browse the table "Events" - delete records you want to delete
5. save the file, move it back to /home/user/.rtcom-eventlogger/el_archive-v1.db on your phone

note: if you have the deleted records on your normal conversations-history, it will be archived again next time...

all right?