iWorship dvds have extremely complex programming. Newer volumes now include the videos in file format which makes it easier to insert into MediaShout as a Video Cue. In order to get subtitles to work, you need PowerDVD 7 or later installed on your computer. MediaShout is designed to use the codecs that get installed with PowerDVD for dvd playback. If you still cannot get subtitles, then there could be other codecs in Windows from another program that are interfering.
NOTE: MediaComplete, LLC is not affiliated with Cyberlink/PowerDVD and does not provide technical support for their products or services. You may also need to install the recommended codec pack and those instructions can be found HERE.