This has now been fixed in version 1.3.1. In your editor module's get_field(...) function, you can use this code to add a style sheet:
This assumes that you included $this->urltoroot=$urltoroot; in your module's load_module(...) function and that your CSS is in styles.css.
Be sure to set Plugin Minimum Question2Answer Version to 1.3.1 in your qa-plugin.php file, since this method won't work in 1.3!
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If you have a question about Q2A, please ask in English.
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