Dear NP3900 users

I am interested in buying a NP3900 but have a few questions:

1) Is it possible to stream MP3 from my NAS (Netgear ReadyNAS) without installing Twonky Software?
2) Is it possible to save playlists (maybe on the NP3900)?
3) Is it possible to enter an url for my favourite internet radio station?
4) What's the range of the WiFi connection? I have my router placed in another room and there are 2 walls between.
(currently have a Chumby for Internet Radio and sometimes the signal is too low)

thanks for answering my questions,
Reto