I'm not sure this has to do with the plugin. Can you play unpacked img-files otherwise? If not, then do this:
Add the filetype under Videos, Video Extensions in Configuration, add .iso also while you're at it.
News in version 0.9.3, released 2012-02-04 (OctaneSnail)
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- Fixed problems loading archives containing a mix of media and non-media files.
- Workaround to allow loading archives with missing LONG_BLOCK flag.
- Workaround to allow loading any part in a multi-volume archive with
MHD_FIRSTVOLUME incorrectly set on all parts.
- A few minor bug fixes.
- Big thanks to John Peterson for reporting the above problems and contributing
patches to solve them.
- Fixed loading archives with unknown file header data.
- Be more lenient when loading multi-volume archives containing multiple files,
if parts are missing, allow complete files found so far to play.
Do anyone have some good solutions to the following issues when using RARFileSource?
- Subtitles included in the RAR file is not found.
- RARs containing iso's can't be played.
- The Dynamic Refresh Rate feature in MP doesn't pick up media-info, thus the default frame rate is always used.
- Extract media-info when importing.
For 1 and 2 the current solution is to manually extract the contents.