I am currently experiencing a problem with a new flynax installation - pictures can't be added to a new listing. See screenshots for clarification:

1. The listing information has been filled out and we arrive at the "Add a picture" page

2. The button is clicked and I select a photo to upload (I have tried many sizes, from very large to very small file size photos) and then click "Open"

3. We return to the "Add a picture" page and nothing happens.

Have you come across this before and if so is it an easy fix?
I thought I may have customised something which caused the error, but I installed a new flynax installation in a different directory and it experienced the same problem.

Note: I have also tried disabling the "Uploading pictures in auto mode", but this also doesn't work. The "Upload" button remains greyed out, even after selecting an image.

I look forward to hearing back.
Thank you.