It is recommended to go with a new subdomain.Reference - https://experienceleague.adobe.com/en/docs/journey-optimizer/using/configuration/delegate-subdomains/about-subdomain-delegation

In the current state, we don't have campaign technical properties on the UI expect for Campaign ID and the output from query service.

You can query ajo_classification_dataset to get the campaign details.

Can you share how the expression fragment looks like ? Ideally, when you place the custom action in the journey canvas, as part of the request parameter mapping - you can pass in string content keeping first name dynamic. 

You can use something on the following lines{%#if equalsIgnoreCase(context.journey.events.`1141761358`._abc.individualId,"hello") %}render_1{%else%}default_content{%/if%}

We have frequency rules that can be leveraged for thisReference - https://experienceleague.adobe.com/en/docs/journey-optimizer/using/configuration/frequency-rules#daily-frequency-cap Other option is to leverage business rules for frequency or suppression logic. You can also explore creating a batch ...

You can query the system datasets by referring to the available fields mentioned in this data dictionary using a Query service connect client like Power BI and extract those details https://experienceleague.adobe.com/tools/ajo-schemas/schema-dictionary.html#_blank 

You can use fragments where in, you won't be able to edit the content unless you break the inheritance. Reference - https://experienceleague.adobe.com/en/docs/journey-optimizer/using/email/design-email/add-content/use-visual-fragments#use-fragmentBut in general, the lock symbol that you see is when ...

This is not feasible as expression fragments can not be consumed in the journey context for passing it as part of the custom action payload.

Can you query these columns from journey step events and see if there is any http error being returned ? _experience.journeyOrchestration.stepEvents.actionExecutionError AS ACTION_ERROR,_experience.journeyOrchestration.stepEvents.actionExecutionErrorCode AS ACTION_ERROR_CODE,_experience.journeyOrche...