Hi utzfu,
I apologize for any frustration with this, and it’s true that outside of the core functionality the two plugins are different in a number of ways.
For example, as you mentioned our free version does not include a File Upload field — we consider this an advanced feature, and so it requires a paid license (of any level) to access. To try and help clarify this, we display an alert when our migration tool is used.
On the flip side, too, our free version can also create unlimited forms and be customized in a bunch of ways that were not provided within the free version for Pirate Forms.
I’m sorry if this specific option felt unclear in any way. If you do decide to continue using WPForms Lite, though, please know that we provide limited, complimentary support for all of our Lite users in our www.remarpro.com forum — and we’d be happy to help if you have questions ??