Thanks for a nice plugin.
I've installed this plugin onto http://frequentbusinesstraveler.com and it is working fine. I removed #comment as comments are being excluded from this theme. All good.
I've also installed it on http://thedieseldriver.com and it is NOT working. I've configured it the same as on FBT. I've checked the theme and wp_footer is there. I do see the CSS and jQuery portions being built out but the upprev_box DIV is not being built anywhere. On FBT it's just before the footer.