Dazzle module, commonly used nowadays, does not work with X-Cart 4.2 branch. Usually its work crashes with the following message:
*Warning*: array_merge() Argument #1 is not an array in *modules/DazzleXML/xml_generation_form.php* on line *21
The reason is pretty simple - $HTTP_GET_VARS and $HTTP_POST VARS arrays are empty. You should just replace them with $_GET and $_POST, after that the module will work properly.
By the way, it is required to check all module/DazzleXML files and make the changes everywhere.
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