Running the FNC Cloud Storage Services Demo and connecting gets
"This site can't be reached. 127.0.0.1 refused to connect"
with both of the Callback URLs above.
We are not aware of any issues with connecting to DropBox from the FNC Cloud Storage Services Demo.
Can you please make sure no other services or applications are running on the same URL + port number?
Also, have you tried restarting your machine?