Without going line for line through the sidebox version of the plugin, my recommendation would be to use the template related files from this plugin: https://www.zen-cart.com/downloads.php?do=file&id=109 such as includes/templates/YOUR_TEMPLATE/templates/tpl_ask_a_question_default.php and includes/modules/pages/ask_a_question (all files within the directory) if using the sidebox "method". At some point I might consider taking a look at the other plugin for an update to bring it in line with current PHP/ZC standards.

Generally speaking the code that I have looked at will likely work without much modification, but it is also a little out-dated (using PHP functions such as eregi_replace instead of preg_replace) and doesn't include some of the improvements that have been made to the front end presentation that would be expected (honey-pot, display of the store's address if so desired/set, notifiers to edit/modify associated data, etc...)

Unfortunately the OP of the code didn't start a thread and that the only place that they appear to have discussed the plugin is within this thread back in 2007 where they were advised to post that code in the sidebox section of the ZC plugins area.