Difficulty uploading files for Daz PA application

isis4444merlin

I am looking for help on how to upload files for my PA application. I followed instructions and have pictures that are 1000x1300 and I have 10 to 11 that I would like to send. Once I filled out the application and chose files, I got the message that there were too many files. I eliminated 3 at a time, same message until I got down to 1 file :- ( . I am trying to show poses so I really would like to submit a group of them. How can I get past this? Do I send multiple batches? Change the size? What size would work?