Sending photos to print at Costco

The problem is with the files you uploaded. It's best not to access the files directly from the iPhoto Library folder. The sanctioned method is to choose the photos in iPhoto, then do File > Export > File Export to a folder on your Desktop. Upload that folder; it will contain the full-sized, edited (if you edited) version of each exported photo. You can trash it when the upload is done, as your photos remain inside the Library.

Regards.

Are you using Costco's Quickupload tool? (Its an internet plugin downloaded from the Costco site)

If yes, when you click the iPhoto icon in the tool (once its activated from Safari) it doesn't show albums, just the Originals and Modified folders and whatever folders are inside your iPhoto library. I find that its too difficult to select my photos this way. (let me know if albums show up for you in this tool.) If you're not selecting from the Originals or Modified folders here, then you are selecting thumbnails which would explain your problem.

I usually export the photos I've saved in an album to a folder on the desktop (temporarily) and then select this folder with the download tool. When the download is complete, the temporary folder on the Desktop can be deleted.

Ive contacts to developer of Picturesync to see if he can add support for costcophotocenter.com
They use shutterfly services, and his app supports shutterfly already.