In the meantime, the solution to avoid the cache, is adding a random number to the URL of your .js (JavaScript) files.
I've asked you to upload the files, to give you a direct solution, but if you can do it by yourself (adapting it to your code), you can try something like this:
<script type="text/javascript">
document.write('\x3Cscript type="text/javascript" src="script.js?r='+ (new Date()).getTime() +'">\x3C/script>');
</script>
Or something like this:
<script>
var axel = Math.random() + "";
var num = axel * 1000000000000000000;
var script = document.createElement('script');
script.setAttribute('type', 'text/javascript');
script.setAttribute('src', 'script2.js?r='+ num +'?');
document.write(script.outerHTML);
</script>
Another possible solution (at server level, without changing your code).
1) In HFS, press Alt+F6 (or go to: Menu -> Other options -> Edit event scripts)
2) When it opens the 'hfs.events' file, paste the following code:
[pre-filter-request]
{.add header|Cache-Control: no-cache, no-store, must-revalidate.}
{.add header|Pragma: no-cache.}
{.add header|Expires: 0.}
This is the most cross-browser headers I've found to avoid cache (supporting HTTP 1.1, HTTP 1.0 and proxy clients). If you only need to support 'HTTP 1.1', then you can skip the last 2 headers ('Pragma: no-cache' and 'Expires: 0').
If my solution has solved your problem, leave a comment here, as reference for other users (in case someone comes with a similar issue in the future).

Hope this helps,
Leo.-