Using MKVMerge to add subtitles
- Open MKVMerge
- Add the movie you will like to have the subtitles added too.
- Add the SRT (Subtitle) file for the movie that you would like to add.
- Click the last track which should be the subtitles.
- Select “EN” for the English language
- Make sure the Forced Track flag is set to yes
- Go to Format Specific Options and make sure the Character set is: pic ISO-8859-2
- Give it a new and click Mux