I experienced and error when activating the plugin (Version 0.11 beta).
Plugin could not be activated because it triggered a <strong>fatal error</strong>. <strong>Parse error</strong>: syntax error, unexpected '"' in <strong>/home/p5_bvffc/site/wp-content/plugins/ultimate-cms/class-inflect.php</strong> on line <strong>32</strong>
On this server I have PHP 5.1.6.
I've tried it on a server with PHP 5.3.1 and it worked with no error.
It seems that PHP 5.1.6 does not support the syntax used in class-inflect.php.
I managed to resolve this issue (on php 5.1.6) by changing the double quotes into simple quotes in the two arrays at the beginning of the file.