I have spent some time off and on reading up on this, attempting various replacement config files and am now learning what these various settings better to write one that works for LMCE and its media players and capabilities. For anyone else poking around with this here is the basics.
Enable transcoding = no by default
- change to yes
File extension open-with instructions = matroska is not included by default
- matroska open with _____ ( i would assume xine but I will try others if needed)
MIME type (?) = .mkv is not understood as matroska for instructions further down the config file
* Where I currently am *
- .mkv does not exist in the MIMI type section where the other file formats are present
- early on in the config file there are MIME type rules for things such as .avi = (name) .mp4 = (name)
- later in the transcoding section, (name) is assigned to a transcoding software instead of file type. Perhaps these MIMEs were grouped early on to save repetition later on?