Hello Wim Peeters,

According to Native odoo behaviour, 

event_lead_rule_skip = True means skip lead creation

Solution would be overwrite following method to allow import process to create lead.

class EventRegistration(models.Model):
    _inherit = 'event.registration'

	​def _load_records_create(self, values):
    """ In import mode: do not run rules those are intended to run when customers
    buy tickets, not when bootstrapping a database. """
    return super(EventRegistration, self.with_context(event_lead_rule_skip=False))._load_records_create(values)

Thanks & Regards,

​

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