Hi!
It has come to my knowledge that me and many other who are using Mediacoder have some difficulty with subtitles. Especially thoose who doesnt even have the subtitle in the list. I my case the subtitle didnt work because Mediacoder has set it to "swe" when its supposed to be set as "sv".
But when I try to put it in manually I only get an error and a programcrash.
Therefor I looked up in the installationsfolder and found prefs.xml.
Just open it with notepad and search for the string
<node key="subtitle"><node key="slang" value="sv"/>
set the "value" to whatever the player MPUI.exe shortens your language to.
It worked for me. At least I now can view it with mplayer(F7 in program).
I might add that I'm using the stable version 0.5.1.
Hope this helps some.