Hello @jeremylanssiers    You should be able to get some good pointers here https://www.slideshare.net/connectwebex/jcr-sling-or-aem-which-api-should-i-use-and-when https://stackoverflow.com/questions/45376376/jcr-api-or-apache-sling     

@Roo In case its an AEM as a Cloud Service instance, you would not be able to set permissions on a running instance on immutable areas.   /apps and /libs are considered immutable areas of AEM as they cannot be changed (create, update, delete) after AEM starts (i.e. at runtime). Any attempt to change...

Hello @RooRue    As per my understanding, "Design" mode is available only for pages created via Static templates. Are you creating the new pages using the same templates as the migrated content?If the designPath configured in the hierarchy of these pages?