[ic] javascript with 5.5.2

[Sales Dept]

In IC 5.5.2 I'm trying to add my own drop down javascript menu in place of 
the comon menu.
I can't figure out where and how to place it, I had no problems with earlier 
versions but with the changes to 5.5.2 I can't get it functioning.
When I use include the whole script shows up.
When I add the following nothing shows or depending on where I put it I get 
a page js/script1.js.html not found.
<script type='text/javascript' src="js/script1.js"></script>
My js folder is in the catalog root.
I believe it's the changes in 5.5 that are confusing me- as I moved this 
script to a currently running version of 5.3 and it works fine.
Any tips or hints would be greatly appreciated.
Steve