Yes you can. There are no limits in this regards. In the fields of the plugin put any text that is up to your needs.
The number of possible columns, rows and tables are unlimited.
All licences have no limits in usage and the payment is one time.
The first plan is like a model of all other plans, making changes on first plan you change other plans at once, that’s why first plan can be used as a column or can be used only as a model and be hidden after the work is complete.
Yes you may upgrade the license by only paying the difference. In this case you may want to contact us.