You have an error in the "featured content gallery" plugin that also uses moo-tools (an older version - 1.11). It says "String contains an invalid character". Disable that plugin and try again. It should work. If it does, then you can either find another solution to your featured content gallery plugin, or either remove the enqueue script for that plugin's call to mootools (because you are already using it in my plugin this may cause conflict if certain calls to the older mootools library are depricated) or call a wp_dequeue_script in your functions file to remove it.
Looking at the code you have, you are actually calling the mootools library three times. Once for the featured content gallery (v1.11), once for my plugin (I'm not sure what version is being used, I should have probably included a version number, but it's available in the file), and once generically by way of google api's (meaning it's being called externally also, likely to the latest version). So, you really should be calling the mootools library only once. If there is code there that calls the latest version from google api's then you should try dequeueing both mine and the one for the other plugin (I will not be updating this so no need to worry about updates, I don't know about the other plugin you are using though), and see if the latest library is compatible with all of the plugins.