Quote Originally Posted by strelitzia View Post
Tested this module out on a clean install of 1.5.4 as that is what it's listed as supporting, but as soon as I enter a model number I get a popup that says
"An unknown response null: :text/html; charset=UTF-8: :Internal Server Error was received while processing an ajax call. The action you requested could not be completed."

No other mods installed. Server is set to PHP 5.6. Database was set to utf-8 at install. Checked all files correctly uploaded. Classic template used for testing.

Any suggestions?
the jscript_framework.php script in your template needs replacing. see:

https://www.zen-cart.com/showthread....t-was-received

play around with that file, as that is where your problem lies....