1. Add OV DCP
2. Add MKV
3. Adjust timeline because the MKV gets placed after the DCP in the timeline (if this is a sane default for the majority I cannot know. For me it isn’t)
4. Right-Click on the MKV and select “advanced settings” and set “Ignore this content’s video …”
5. Select Audio Tab on MKV and deselect the channels (unsure if this is needed)
6. Right on the OV DCP and select “Set project markers from this DCP”
7. Go to “Timed Text” tab on the MKV, choose “Use as open subtitles”, set “Language” and select “Stream” (fra in this case)

Now I go back to the player and skip to a place where there is a subtitle and see if the position/size/language etc. is correct. That’s where it usually freezes.