Thank you Mark for your response. The problem I am having is with Vimeo Pro and the HLS link they provide. The mp4 links load no problem but he HLS link won't load at all.
Vimeo does a redirect on the HLS link and was curious if anyone at Roku knows how to get this working?
To work around it, you should do a HEAD request on the URL using the roUrlTransfer component first, then set the stream URL to the value of the Location header.
Am getting nowhere with this too fast.
Doing the head request recommended by TheEndless and using the response as the URL, or even reading the contents of that response and saving it to tmp, then playing the source through server code in brightscript where the roku itself feeds the top level m3u8 doesn't want to work (this code is tested and works normally, we use it to embed intros and extros at runtime when playing m3u8's through Azure).
When (if) I find a solution that works I'll post the code here.