Hello,
When you have activated the site, FSQM would create 5 tables, wp_fsq_form, wp_fsq_data, wp_fsq_files, wp_fsq_category, wp_fsq_payment. You need to make sure those tables are present in your new site. I would recommend deleting those tables on your new site and deactivate/activate FSQM Pro which would create a fresh set of tables.
Then you can export/import the table data from old installation to new installation.
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