[Plugin: Dynamic "To Top" Plugin] Button does not show

Website: http://www.catimbang.com/
Browsers: Mozilla/Chrome (all in latest versions)
WordPress: 3.4 Multi-site
Plugins activated:

Dynamic to Top
Sociable
W3 Total Cache
WooTumblog
Wordpress SEO by Yoast

Dynamic to Top: Version 3.2

Note:
I have correctly installed the plugin, setup and saved changes. However, it did not show up in my site. Please advice.

Thanks!

http://wordpress.org/extend/plugins/dynamic-to-top/