Not sure where to look at this point!
I've used this plugin on a website. It works perfectly on my development server, but not on the live hosting. I can't access error logs for the live hosting unfortunately.
When the form is submitted, it just comes back to the page. It uploads the file and what not, but doesn't add the picture, doesn't email, and doesn't output any error whatsoever.
I should add, NextGEN works fine when images are added from the backend