ith3 it's a different program so you don't have to mix them, but yo nee to keep both in separate folder; ith3 doesn't replace ith 2.3 so you need both.
If the updater fail, then download all files from here
https://interactive-text-hooker.googlecode.com/svn/project/ITH3/Release/
including the profile folder and what's inside, and put everything inside your preferred empty older.
The updater is meant to keep the files you have locally in sync with the ones you find on that url, but if it won't work, periodically (try every month) manually check the date of the files and whta's added in profile folder, then get and replace what's changed.
edit: i noticed that the webserver doesn't show neither the date and the size, you can compare the crc in index.html with your files, or just download and overwrite everything periodically.
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