Hi Filippo,
You know, I am not totally sure whether Event Tickets Plus and the Name Your Price plugins are compatible with one another.
Our ticket purchase form is close to the WooCommerce Add to Cart Form, but might be missing a hook that the plugin needs.
Our form can be customized in the theme so it could be modified there if it needs to be updated for any reason at all, though I do not have any other information on how that would work out.
We do offer 30 day refund policy so you could try it out and if it does not work request one.
Let me know if you have any follow up questions.
Cheers!
Geoff