In init.php (confirmed against your GitHub copy at https://github.com/bradp/wpTextResize/blob/master/init.php) there is no closing '?>'
Another issue, albeit less serious, is the use of the PHP shorthand '<?' to open PHP blocks (as opposed to '<?php').
Once those tweaks are made, I can confirm the plugin works (in my circumstances anyway).
I'd have slung you something via GitHub, but haven't opted in to an account yet...