[applebyter]

The files are on my NAS in a share called media. My folder structure is:
Videos\TV Shows\The Hitchhiker's Guide to the Galaxy\tvshow.nfo
Videos\TV Shows\The Hitchhiker's Guide to the Galaxy\Episode 1.mkv
Videos\TV Shows\The Hitchhiker's Guide to the Galaxy\Episode 1.nfo
Videos\TV Shows\The Hitchhiker's Guide to the Galaxy\Episode 1.tbn
Videos\TV Shows\The Hitchhiker's Guide to the Galaxy\folder.jpg
Videos\TV Shows\The Hitchhiker's Guide to the Galaxy\fanart.jpg
...
All the other episodes for that show follow the same naming format, just numbered 2 to 6.

Can you elaborate on your comment that the tvshow.nfo file seems incorrect? I probably have tags in there not used by XBMC, but all of the tvshow.nfo files will have the same tags and it is only a small handful that aren't displaying their episodes. I am assuming that XBMC's XML parser is bright enough to ignore tags it doesn't know.

An example of a show where XBMC is scanning the episodes correctly would be:
Videos\TV Shows\The Martian Cronicles\tvshow.nfo
Videos\TV Shows\The Martian Cronicles\1x01 - The Expeditions.avi
Videos\TV Shows\The Martian Cronicles\1x01 - The Expeditions.nfo
Videos\TV Shows\The Martian Cronicles\1x01 - The Expeditions.tbn
Videos\TV Shows\The Martian Cronicles\folder.jpg
Videos\TV Shows\The Martian Cronicles\fanart.jpg
...

The tvshow.nfo file is

Code:

<?xml version="1.0" encoding="utf-8"?>
<tvshow xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <title>The Martian Chronicles</title>
  <rating>6.7</rating>
  <genre>Sci-Fi</genre>
  <mpaa>TV-PG</mpaa>
  <premiered>1980-01-27</premiered>
  <studio>BBC</studio>
  <plot>Ray Bradbury's subtle, elegant fantasy of man's earliest experiences on an alien planet was given the big treatment in this three-part American adaptation. Rock Hudson starred as the pivotal character of Col. John Wilder, leader of a successful expedition to Mars who finds his sympathies torn, but who is helpless to prevent the planet being raped by American culture.</plot>
  <actor>
    <name>Rock Hudson</name>
    <role>Col. John Wilder</role>
    <thumb />
  </actor>
  <actor>
    <name>Gayle Hunnicutt</name>
    <role>Ruth Wilder</role>
    <thumb />
  </actor>
  <actor>
    <name>Bernie Casey</name>
    <role>Maj. Jeff Spender</role>
    <thumb />
  </actor>
  <actor>
    <name>Christopher Connelly</name>
    <role>Ben Driscoll</role>
    <thumb />
  </actor>
  <actor>
    <name>Nicholas Hammond</name>
    <role>Commander Arthur Black</role>
    <thumb />
  </actor>
  <actor>
    <name>Darren McGavin</name>
    <role>Sam Parkhill</role>
    <thumb />
  </actor>
  <actor>
    <name>Roddy McDowall</name>
    <role>Father Stone</role>
    <thumb />
  </actor>
  <actor>
    <name>Bernadette Peters</name>
    <role>Genevieve Seltzer</role>
    <thumb />
  </actor>
  <actor>
    <name>Joyce van Patten</name>
    <role>Elma Parkhill</role>
    <thumb />
  </actor>
</tvshow>

The first episode's NFO file (1x01 - The Expeditions.nfo) is:

Code:

<?xml version="1.0" encoding="utf-8"?>
<episodedetails>
  <title>The Expeditions</title>
  <runtime>98</runtime>
  <aired>1980-01-27</aired>
  <rating>6.7</rating>
  <season>1</season>
  <episode>1</episode>
  <plot>January 1999: The Zeus Project makes its first manned flight to Mars. Its ultimate goal: colonisation. On Mars, Ylla dreams of the coming astronauts and her husband, Mr K, plots their doom...
The second expedition lands and finds a Mars a deceptively familiar but deadly home from home.
Finally, Col. Wilder's Zeus III expedition arrives to find the Martians dead, wiped out by chicken pox. For one crew member, Spender, the thought of Earth culture tearing the planet apart is too much to bear.</plot>
  <credits>Ray Bradbury (writer) /  Richard Matheson (writer)</credits>
  <director>Michael Anderson</director>
</episodedetails>