Hello everyone,
and apologies for not having replied to this topic in a long time. At the moment, as you noticed, there’s a fixed set of custom fields available when using the Cpt block in the Composer. We tried to make it simple to create a new custom block (starting from the Cpt block itself) in order to map and show every custom field you may need. But I get this isn’t for everybody. I will talk with our devs to evaluate further developments on this matter.
Michael