Long,
Thanks for your suggestion that we talke a look at the Model.php file. Having done so we've managed to achieve 99% of what we need.
One final issue remains...how can we change the Primary Column. MB Custom Table inserts the 'id' column and this has the row actions within in. We are looking to move these row actions to another column. We would usually have used the following filter 'list_table_primary_column' but this seems not to have an effect.
Thanks,
Will