There is no convention in the Photopost program to rename filenames. Titles yes but not image names as there would never be a need the image is uploaded processed and there.
You can not rename the files unless you want to break Photopost. Remember the filenames are all stored in the bigimage field in the photos table so if you rename them then you effectively delete the photos from Photopost cause you will get a broken picture.
ok my last question for this thread.
i am more concerend about google indexing of my images, does photo title (if persent in alt tag) gets a photo indexed in search engine with the title name ?