I recently upgraded to Flashlight 1.5.1 along with WooCommerce 1.4.2. Please be advised the the WooCommerce plugin changes file permission rights without notification through their install process. This has caused numerous problems in installing other plugins until I finally became aware of what was going on.
Also, the Flashlight update 1.5.1 does not install into a new directory. I first had to uninstall Flashlight 1.4 then install 1.5.1. A suggestion is to install all updates into new directories.