Very strange. I'm using the default WordPress function calls to write and read the plugin settings. Maybe something is wrong with your MySQL database or your WordPress installation. But it's still confusing that other plugins work fine. Have you tried installing a random plugin you haven't used before and see if the configuration works there?
The plugin should work with every text as long as you have set up your preferred language and the class name correctly. Since version 4.0.0 you can force a language even if the lang-attribute is not used in your template. In case of your blog named like your username the class "entry-content" (without quotes) would be correct. Do you know how to write CSS?
If Hyphenator is activated and configured you should see something like this in the source code of your website:
<!-- Hyphenator for WordPress -->
The default configuration uses the class name "hyphenate" and needs a lang-attribute in the HTML structure. Otherwise it won't work.