The plugin worked just fine for me.... Until now.
Now I only get the error message, that the shared folder is not readable.
I tried creating new folders in Dropbox, moving the folders to other subfolde, changing the link form https:// to http:// etc. but still couldn't fix the problem.
I even tried downgrading the plugin to 1.2 once but couldn't get rid of the error message.
You seem to have the same problems with your demos on your side!
Would be nice if you can fix it asap!
Loved the plugin before and wasn't able to find one quite good as yours!