Unfortunately there is no public API available to do so.Though you could use XML Deployment packages to import the events + transactional messages.After the import, you would then only have to publish both the event and the message via the UI

Unfortunately you can only update by labels not by an ID.

FOr bulk imports any workflow is needed, not necessarily an import template or workflow template. The template view has no create buttons, that's right.Though you can hover over an existing template / click the ... icon (depending on browser) and then choose duplicate to create a new one

Few things you could do:add a condition on the delivery ID in the brand config to only reflect it for the requested deliverycontext.delivery.name == 'DM123'or do a filter on the URL to check if a parameter was already defined on the URL and only append from branding if it's not yet there$(urlstring)...

it should fill the Pkey with the right values.Though it will only work for "real" profiles, i.e. when sending a proof to a test profile it won't include a pkey value.

Unfortunately with ACS you can't send any files as attachments. Depending on the record count,you may render it as personalized content.But for anything > 10 rows, that won't really be a good approach

Unfortunately the API currently does not expose anything on the delivery information. Only way to make this available:Create a custom resource with the needed fieldsCreate a technical workflow which synchronizes the information from the deliveries to the custom resourceThe custom resource will then ...

To get that working, you would need to:Define an enrichmentinside the enrichment add the target schema and choose type = collection.Note: here you need to define a max number of items to fetch, unfortunately you can't easily loop over an unlimited setthen add the required fields as target data in th...

the subscription indeed only works for profiles in the Campaign database.So for importing new users, you first need to create the profile and afterwards you can assign it to the service

indeed you can't configure target data on test profiles To test it completly, you need to use profile substitution feature:https://experienceleague.adobe.com/docs/campaign-standard-learn/tutorials/communication-channels/email/profile-substitution.html?lang=en