1) is Ethernet connection to router required ? - as current TiVo is in lounge - ground floor at front of house & router is in bedroom - first floor rear of house. ....... With no Ethernet cable connection between them
2) Can series links (& recordings be transferred from outgoing TiVo to incoming V6
1) Ethernet preferred but you can use powerline adapters or wifi, assuming a suitably stable and strong signal at the V6 location. Personally, I use powerline adapters, Netgear PL1000s.
2) You can indeed transfer series links, wishlists and thumbs from your old TiVo to your new V6. You can't transfer existing recordings although you may consider keeping your existing TiVo, at a cost, until you watch all its recordings.