I did some tests, I corrected the paths into package-info.xml but without success
<require-file name="Tags.controller.php" destination="CONTROLLERDIR" />
<require-file name="Tags.subs.php" destination="SUBSDIR" />
<require-file name="Tags.template.php" destination="$themedir" />
<require-file name="Tags.english.php" destination="$languagedir" />
<require-file name="tags.css" destination="$themedir/css" />
<require-file name="tags.js" destination="$themedir/script" />
should be
<require-file name="Tags.controller.php" destination="CONTROLLERDIR" />
<require-file name="Tags.subs.php" destination="SUBSDIR" />
<require-file name="Tags.template.php" destination="THEMEDIR" />
<require-file name="Tags.english.php" destination="LANGUAGEDIR/english" />
<require-file name="tags.css" destination="THEMEDIR/css" />
<require-file name="tags.js" destination="THEMEDIR/scripts" />
same paths should be applied to uninstall, but the problem is this:
<hook hook="integrate_mark_read_button" file="SOURCEDIR/subs/TabularCategories.subs.php" function="tabular_categories" />
which has nothing to do with this addon and I have no idea how to integrate the hooks from this add-on.
Anyway Emanuele mentioned that this version is not developed anymore:
At this point let's hope that @emanuele will have soon a working internet connection and find the time to fix this add-on.