I'm running LE with the Xonfluence skin. Since I switched ffrom OpenElec to LibreElec the "In Progress TV shows" menu button in Xonfluence hasn't worked. I have asked the author of Xonfluence (helly) what the problem might be, and with his excellent support (kudos!) it became immediately clear that the file ~/.kodi/userdata/library/video/inprogressshows.xml is missing on LE. In fact, so is the ~/.kodi/userdata/library/video subdirectory; there is nothing under ~/.kodi/userdata/library.
I have created the "video" subdirectory under library and put helly's inprogressshows.xml file there, and now the "In progress TV shows" menubutton works. In other words, the fact that this file is not included in LE causes the "In progress TV shows" navigation button not to work.
While in my case this problem (the missing XML file) was exposed in Xonfluence, other skins might be similarly affected.
Contents of inprogressshows.xml:
<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<node order="4" type="filter" visible="Library.HasContent(TVShows)">
<label>626</label>
<icon>DefaultInProgressShows.png</icon>
<content>tvshows</content>
<rule field="inprogress" operator="true" />
</node>I have only looked at LE8, so I'm not sure if this problem still exists in LE9. If it does, simply adding the missing subdirectory and file will fix it. 
