Do you get anything if you turn WP_DEBUG on?
If unfamiliar, in wp-config, add this:
define( 'WP_DEBUG', true );
More Info:
https://codex.wordpress.org/WP_DEBUG
That does’nt sound like a browser problem. 60 secons might be too short.
I did not use this plugin yet so I’m not sure about the memory usage.
However, if it is iterating over a potentionally large dataset you might run out of memory as well.
You should be able to temporarily circumvent these limitations by putting the following lines in ( for example ) wp-config.php.
ini_set(‘max_execution_time’, 600); // 10 minutes, no time limit = 0
ini_set(‘memory_limit’,’128M’);
If this is not permitted by your hosting company you should seriously consider spending a little more on hosting. You might want to look at cloud hosting. ( And basically just pay for what you use ).
I would get you to try what the others have suggested and report back with your findings.
Though next time I would encourage you to open a support ticket for your problem rather than leaving a negative review as it’s most likely a problem that we can work through and solve for you.