I tried-out your plugin today, and the button text is repeating so that it shows on the button twice. The two test-buttons I tried were named: apply now and test button. The text for both buttons repeated as: apply now apply now and test button test button. It may be a conflict with another plugin or something but I just uninstalled it because I don't have the time to disable and re-enable plugins. When I tried it in compatibility mode, etc. the code displayed as raw text, but no buttons at all.