step 1, download q2a 1.7.4
step 2, download this plugin
step 3, unzip q2a, let's just say the extracted folder is q2a
step 4, unzip the plugin into q2a/qa-plugin
step 5, follow this guide to install q2a
step 6, plugin will be enabled automatically.
note, plugin has been tested with q2a 1.7.4 only