Okay, I've successfully uploaded the file and got it to insert the name of the file into the table. I uploaded another picture with the same name again to a new record and it successfully renamed the picture in the images file adding an '_1'. But the name in the table didn't get an underscore.
Also I attach a screenshot of 'page two' of the insert wizard. What do I put in in the File entry section/field where the default is [filename]