You can connect the Roamio to a local PC or other file share and play movies from that using using either TiVo desktop or the community developed PyTiVo.
Really, it is a much better solution and I think I gives you exactly what you are looking for.
TiVo S2 (Retired)(lifetime transfer)
TiVo Series 3 (Sold)
TiVo HD (Sold)
TiVo Premier (2 TB Upgrade)
TiVo Roamio Plus
iPad TiVo app