jQuery LockFixed will not work

[treeguy]

I have been unable to get LockFixed to work on my server. As a quick test, I uploaded the source code of the LockFixed demo file to my server (https://store.advancedtree.com/agora.cgi?cartlink=DEMO-Lockfixed.shtm; put jquery.lockfixed.js in that directory, also), but the "stickiness" of the menu/sidebar and its underneath stacked element do not work. By the way, I changed the demo file's extension to *.shtm because the site has code that automatically populates a menu from any *.htm or *.html files. Am I missing a needed path declaration or something?
Thanks in advance,
John