I tried this with my Roku 2 and using the Roku Media Player channel. UMS did recognize my Roku, but video still did not play. I let the player sit in the 'playing' state (not playing) until it went back to the menu on its own.
Here's the log:
11-03 19:52:13 Started playing Saturday.Night.Live.S40E04.Jim.Carrey-Iggy.Azalea.HDTV.x264-CROOKS.mp4 on your Roku 3
11-03 19:52:19 Stopped playing Saturday.Night.Live.S40E04.Jim.Carrey-Iggy.Azalea.HDTV.x264-CROOKS.mp4 on your Roku 3
11-03 19:53:40 Started playing The.Big.Bang.Theory.S08E07.HDTV.x264-LOL.mp4 on your Roku 3
11-03 19:55:48 Stopped playing The.Big.Bang.Theory.S08E07.HDTV.x264-LOL.mp4 on your Roku 3
And some debug info:
DEBUG 2014-11-03 19:53:40.803 [StartPlaying Event] The full filename of which is: C:\Users\Drew\Downloads\The.Big.Bang.Theory.S08E07.HDTV.x264-LOL.mp4 and the address of the renderer is: 192.168.1.167
DEBUG 2014-11-03 19:54:07.379 [AWT-EventQueue-0] Checking dbgpack property in UMS.conf
DEBUG 2014-11-03 19:54:07.379 [AWT-EventQueue-0] Reading dbgpack: default: null, previous: "extras\channels\channel.log", current: "extras\channels\channel.log,C:\Program Files (x86)\Universal Media Server\extras\channels\channel.log"
DEBUG 2014-11-03 19:54:07.379 [AWT-EventQueue-0] adding extras\channels\channel.log
DEBUG 2014-11-03 19:54:07.379 [AWT-EventQueue-0] adding C:\Program Files (x86)\Universal Media Server\extras\channels\channel.log
DEBUG 2014-11-03 19:54:07.379 [AWT-EventQueue-0] adding C:\Program Files (x86)\Universal Media Server\renderers\Roku-Roku3.conf
DEBUG 2014-11-03 19:54:07.380 [AWT-EventQueue-0] adding C:\Program Files (x86)\Universal Media Server\renderers\Apple-iDevice.conf
DEBUG 2014-11-03 19:54:07.380 [AWT-EventQueue-0] adding C:\ProgramData\UMS\WEB.conf
DEBUG 2014-11-03 19:54:07.380 [AWT-EventQueue-0] adding C:\ProgramData\UMS\UMS.conf
DEBUG 2014-11-03 19:54:07.380 [AWT-EventQueue-0] adding C:\ProgramData\UMS\debug.log.prev
DEBUG 2014-11-03 19:54:07.380 [AWT-EventQueue-0] adding C:\ProgramData\UMS\debug.log
DEBUG 2014-11-03 19:54:21.363 [UPNP-AliveMessageSender] Sending ALIVE...
DEBUG 2014-11-03 19:54:21.547 [New I/O worker #3] HTTP User-Agent: Mozilla/4.0 (Compatible, Aggregation, Twonky, 7.0.10-Android ) DLNADOC/1.50
INFO 2014-11-03 19:55:48.805 [StopPlaying Event] Stopped playing The.Big.Bang.Theory.S08E07.HDTV.x264-LOL.mp4 on your Roku 3
DEBUG 2014-11-03 19:55:48.807 [StopPlaying Event] The full filename of which is: C:\Users\Drew\Downloads\The.Big.Bang.Theory.S08E07.HDTV.x264-LOL.mp4 and the address of the renderer is: 192.168.1.167