It is Linux only at the moment, but here is a new TiVo To Go channel.
https://github.com/tivoguy/TiVoToGo.bundle
This uses the TiVo To Go API to allow you to watch a stream of a recorded show, or to download the show to a folder.
Sadly the TiVo To Go API does not allow random positioning or an offset into a show, so if you advance past the point you have downloaded while watching live, the stream will restart.
I only tried this with a TiVo 2 tuner premiere because it is all I own.
Best of Luck,
TiVo Guy