When uploading a picture using the "simple upload" button, it uploads it to a different group. In my case, it was uploading it to group #1 when I was trying to upload it in group 19.
Reinstalled the newest version of PhotoGroup. The trouble is in. When using simple upload (i.e. mobile device) the plugin tries to submit the image to the group with id=1 (when it is not available - just do nothing). Please review.