If you want to use relative path names instead of full path names for images, you can try now a beta version. Download the zip file and copy the content into the Diving Log 6.0 program folder (please check if you have version 6.0.21 installed before applying the update).
This feature is splitted into two parts. First you can activate relative path names for new images that you add to your logbook:
The 2nd part is available in the Photo Manager, which now shows all images within your logbook. You can easily select one or more lines and convert all selected image path names from absolute to relative path names (relative to the logbook file location):
You can use both types of path names in your logbook and switch back and forth. Let me know if you find any issues like missing images with relative path names.