I'm trying to upload an image (tried png, jpg) to my wagn with an admin account and as soon as I click submit, I instantly get the grey wagn background with 'false' as text in all lowercase and very thin font. And the user process running wagn does have full write access to all the wagn directories.
Interesting. I tried and was unable to reproduce this locally. Is there any helpful information in the log files? You definitely have permission on the local/files directory? (that's the default directory for uploads)