Custom Post Types Import Field Mapping

I try to import Custom Post Type. The field mapping doesn’t show any fields at all, after choosing my custom post type.
The console returns some errors:

Uncaught TypeError: Cannot read property ‘value’ of null ultimate-importer-free.js:3

Uncaught TypeError: Cannot read property ‘value’ of null dashchart.js:2

Failed to load resource: the server responded with a status of 500 (Internal Server Error) admin.php?page=wp-ultimate-csv-importer/index.php&__module=custompost&step=mapping_settings
—
The ‘null’ value is on the line with var “checkmodule = document.getElementById(‘checkmodule’).value;”
and
“var get_module = document.getElementById(‘checkmodule’).value;”

The Element with this id indeed is not present in the source code..

Btw. the plugin is great and I use it quite some time. However, things which used to work doesn’t work anymore and free features like category and tags were removed from the free version. And these are probably some really bad news for users.. Pity.

https://www.ads-software.com/plugins/wp-ultimate-csv-importer/