After updating Live the touchAble script is missing

The scriptfolder "touchAble" resides inside the application itself (Mac) / application folder (Windows).
As with every update Ableton installs a new instance of Live and leaves the old ones untouched, you have to install our server-software into this new instance of Live.
The same advice is valid if you use different instances of Live: Please redo the installation for each instance of Live.