AGG 0.2.4 added two features, that are more-or-less designed to work together: Export Rename List and Prefix Filenames.

Prefix Filenames

Clicking Gallery->Prefix Filenames will add numeric prefixes to the output file names; Initially the output file names are the same as input. For example, if you had just two images, PIC_0001.JPG and IMG_2031.JPG, the Prefix Filenames will turn them into 00PIC_0001.JPG and 01IMG_2031.JPG.

This feature is handy if you want to have the images sorted the same way as they are in the gallery project, when viewed with, e.g. Windows Explorer - the images are sorted alphabetically and appear in correct order, because of the numeric prefixes.

Export Rename List

Located in File->Export Rename List...; when you click it, you will choose a file where the rename list is to be saved. Then, the dialog asks you for a "Rename command" (you should type "ren" if you are running Windows, or "mv" if running Linux/OS X). The file will contain a list of files (two file names per line): the input image name, and the output image name (without any directory prefixes). So the rename list file will contain a mapping between the input and output images. Using the aforementioned "rename command" you can turn this file into a .BAT file (Windows), or a shell script (Unix), that will rename your photos without making any gallery. This is useful in conjunction with Prefix Filenames and Time Offset - see below for an example.

Using Export Rename List in conjunction with Prefix Filenames and Time Offset

Using these three features, you can time-offset your photo collection, so that the images appear sorted when viewed in any file browser, or any photo-viewing program, etc. That way, you can time-synchronize photos not only in the output galleries, but within your photo collection as well!
Here are the steps to do this:

1. Create a gallery project with your (unsorted) photos from several cameras (all images must be placed in the same directory). Do not setup this project much - it will be discarded later;
2. Use Time Offset to order the photos chronologically;
3. Use Prefix Filenames to make the ordering permanent (in the sense it is preserved in alphabetical file name sorting);
4. Use Export Rename List to create a .BAT file (Windows) or a shell script (.SH, Linux/Mac OS X), and use "ren" as rename command (Windows) or "mv" (Linux/OS X). You should save the rename file in the directory, containing the input images;
5. Run the generated rename file (Windows: doubleclick on the .bat file; Linux/OS X: from a terminal, use "cd" to navigate to the directory with the images, and then run "sh rename_list_shell_script"). This will do the actual renaming;
6. (optional) The AGG project is no longer valid. Close it and create a new project. The images will already be sorted there, no need for Time Offset in that project;
7. (optional) Create your gallery as usual.