Well I think I may have figured out the first issue with using Tversity's HLS for the roku. When just playing a m3u8 url from tversity on the roku using the simplevideplayer example, the progress bar would go about a third of the way across and then stop (this appears to indicate that the m3u8 files has loaded, but no segments). I noticed that the urls in the tversity m3u8 were relative, not absolute:
#EXTM3U
#EXT-X-TARGETDURATION:1
#EXTINF:10,
/getres/profile/ebe80805-5640-4753-b0ad-e3f53817ae2f/video/mp2tavc;res=1280x720;fps=30_1;vb=2000000/range/0-437852/7184/segment.ts
#EXTINF:1,
/getres/profile/ebe80805-5640-4753-b0ad-e3f53817ae2f/video/mp2tavc;res=1280x720;fps=30_1;vb=2000000/range/437852-503652/7184/segment.ts
#EXTINF:2,
/getres/profile/ebe80805-5640-4753-b0ad-e3f53817ae2f/video/mp2tavc;res=1280x720;fps=30_1;vb=2000000/range/503652-632244/7184/segment.ts
#EXTINF:2,
/getres/profile/ebe80805-5640-4753-b0ad-e3f53817ae2f/video/mp2tavc;res=1280x720;fps=30_1;vb=2000000/range/632244-761212/7184/segment.ts
The HLS spec says you can use relative urls, and that is what the examples in simplevideo player use, however the simplevideoplayer sample urls are relative to the directory containing the m3u8 files. The Tversity m3u8 urls are relative to the server root. I think Roku may not handle urls relative to the server root correctly for HLS (just a theory).
Anyway, I copied the full m3u8 file, put in the full IP and port information for Tversity and placed the file elsewhere on the server. This improved the situation, the progress bar will jump to around 1/3 full (again, I assume this indicates the m3u8 file has been loaded), then it will slowly progress till over halfway and then stop. I assume the slow progression represents the loading of the individual segments. I can't figure out why it stops though.