Hi Jos

Gallery 2.4.2 inserts the Template JavaScript code twice into the page when
smarty comments are used in the js-template box.
The first time where you have choosen to insert  the javascript code, either in
the header or at the bottom of the body. The second time it inserts it just
after the {Gallery}-Tag and after that inserts a closing smarty comment '*}' 
which shows up at the end of the gallery.

The simplest solution would be to put a note behind the name of the js-template
box, something like:
"Template JavaScript: (you may use smarty but no smarty comment eg. {* smarty
comment *}".
Another solution would be to handle the smarty comment in your code.

Anyway I thank you, Jos, very much for your effort you put into this great
module and in cmsms as a whole.