As a user I would like to have a way to include custom bpmn types or, at least, have the possibility to apply templates to types that are not used explicitly by the engine, while running.

Trying to 'decompose' our request, let us give you some more context:

• in our ecosystem, Camunda is used as a bpmn/process engine, but User tasks are managed by a microservice and shown in a external application,
• to execute a process in the external application, we need to assure that several micro-services are correctly configured: for example, for each task, we need to setup several configuration files, for something similar to a timer (we call it clock), we also need to specify some other config files (for the clock microservice)...
• to accelerate process deployment, we built a tool that, based in the bpmn, creates all the needed configuration fileas, as well as manages git conections and other needs that we have to assure process execution.
• while evolving our tool, we felt the need for a change in the modeler: we would like to have the possibility to
  • create custom bpmn types and, if not possible,
  • use a template for the 'data objecte reference' or 'text annotation', that would allow us to introduce specific properties and, therefore, identify which type of 'service' we're modeling and corresponding needed properties