My question relates strongly to Magento 2: Error 500 with correct Password in Magmi.ini
However I am not running PHP 7.1 but running PHP7.2.27 on centos 6 but still getting the sodium crypto error when using current version from github here https://github.com/macopedia/magmi-m2
when I try to use the version for php7.1 i get error returned
Performing Datasource Lookup...
Warning: fopen(/var/import/import.csv): failed to open stream: No such file or directory in /inc/magmi_csvreader.php on line 51
Warning: count(): Parameter must be an array or an object that implements Countable in /inc/magmi_mixin.php on line 28