Hi,
ok, I had another look with the other account that you sent, and with that I can reproduce the issue, and I think I might have found the cause. The problem seems to be related to the database. All relevant entries in the wp_postmeta
database table for the TablePress tables are missing. In those entries, TablePress e.g. stores the individual settings/checkboxes of a table, but also the visibility settings of the rows and columns.
If those are missing, the table will be hidden. Also, when they are missing, the table can not be copied which caused the other error message.
To fix this, you will have to save each table at least once and then restore some default values. Mainly, that is the checkbox settings, but more importantly the visibility. So, whenever a table is not shown, go to the “Edit” screen of that table. It is then probably shown in red color. This means that the rows/columns are marked as hidden. You can then click all the checkboxes on the left of the rows and below the columns (if you hold down the Shift key, you can select multiple checkboxes at once). Then, use the “Selected rows/columns: Show” button to make them visible again (so that they are not marked in red).
Regards,
Tobias