Does anyone know how to install the model designer for creating workflows with the Activiti engine? From business processes I already have drawn, I want to create a BPMN 2.0 variant. But for this I need the appropriate designer to be able to draw processes in Share (I assume it is not to be done in Explorer).
If you are talking about the Eclipse Activiti plug-in, see this page.
If you are talking about a web-based Activiti designer, see this page, however that would only work for standalone Activiti. I don't know of anyone that has integrated it with Community Edition.
Both possibilities are "outside Alfresco" applications. So if I understand well, designing a process must be done outside Alfresco at the moment, and can not be done in the Share gui as I expected?