Hi,
1) You'll need to create a header for the HTTP basic authentication, which takes the values from the -u parameter.
2) For URL-encoding the data, there's currently no ready-to-use node. (would be nice to have)
So you'll have to resort to some Java scripting for both. For (1) I have a ready-to-use example. Get in touch via email if you're interested.
Kind regards,
Philipp