Hi Pete,
ah, I found the reason for the problems on your site: Your theme is also loading a copy of the DataTables JS files (from /wp-content/themes/realexpert/js/jquery.dataTables.min.js). However, it’s loading an old version (version 1.9.4), while TablePress brings version 1.10.3.
As the copy that the theme brings is loaded first, that’s the one that will be used. Now, unfortunately, that older version uses a different code syntax, so that the JS commands that TablePress uses natively (as well as the “Custom Commands”) don’t work. This is for example also the reason why you are still only getting the pagination with 10 rows, although you have set the value to 50.
The best fix here would be to stop the theme from loading DataTables at all, as you are probably not using other tables besides those from TablePress. An alternative would be to replace the content of that JS file from above with the content of the DataTables JS file from TablePress. That way, everything should work fine (but you’d still be loading the same content twice).
Regards,
Tobias