I have been trying for a few days to get a functional fast forward as opposed to skipping forward some number of seconds.
Even when I change FF/RW behaviour to fast play, it still is skipping. Does NextPVR not really do FF? Does it just skip forward and back?
Yes, fast play does repeated short skips. On my machine it's as smooth as my DVD play's fastforward. I see a frame about every half second.
The reason it does this is because there is no standard way to in directshow decoders to do faster than 2x playback, and no standard way to backward playback at all. If you're curious how some commercial apps can do this - they depend on special proprietary APIs on their own supplied decoders to implement this. NextPVR doesn't ship with decoders, and instead has to work with any old decoders the user already has on their machine, and repeated short skips are the best generic way to emulate this across all decoders.
XBMC [Kodi etc.] have nice smooth ff/rw and skips...you can use it as a client on server machine and elsewhere.
