I only know of one other functional DLNA player for Roku devices (other than RMP), and that is Chaneru. However, I don't think development has continued with it. I do know that when I was using it before RMP was released, it was extremely slow to use. I don't think it has much improvement in the video playback. Chaneru also offers its own server product, so perhaps it works better with that. Plex and Emby player channels cannot connect to DLNA servers, only their own server products (their servers do offer a DLNA output, but the players won't see the DLNA side).
That said, RMP does show time elapsed and time remaining if you pause the playback. I tested this with both video and music. Yeah, not convenient to pause playback to see those numbers. But they are there.
Of course, RMP hasn't received any real updates in close to two years, so no idea what Roku is doing with it now. Hopefully they will put a developer in charge of it that cares about how it works.
EDIT: I just reinstalled Chaneru and at least on my Ultra 4800 the channel won't even load. As I mentioned, I don't think development has continued with this channel, so RMP may be the only channel option left for DLNA playback.
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