Yes. Real time authentication. There is no other way to do it.
Only when submit button is clicked. For now. By stable release it will be settable.
Works for me.
On our test server we have an attribute called "ipphone", we have set the "Extension Link Attribute" to "iphone". When the sync happens if "ipphone" is set to a valid extension (that is not previously assigned) it will be set to that user automatically.
You'd have to give examples of a filter you'd like to provide.
I don't know what it would look like or how that would even function
http://wiki.freepbx.org/display/FPG/How+to+Authenticate+User+Manager+via+Microsoft+Active+Directory