We discuss questions about user centric development of business process modeling notations. In the center of our research there is a fully featured multi-enterprise business process platform (ME-BPP) based on the concepts of agent-based business processes, which builds on the formal foundations of the subject-oriented business process management methodology (S-BPM). The platform is implemented based on cloud technology using commercial services. Additionally we developed a "block modeling" technique to find a semantically transparent modeling notation which can be used by novice users to model subject-oriented business process (S-BPM) models. As this is ongoing research there are still serious open questions. But, the presented approach breaks with some of the rules of typical process modeling notations and hopefully stimulates innovation. Additionally we want to continue our research towards the enhancement of our modeling approach towards a user centric "syntax and semantic free" modeling technique to develop user and domain specific modeling notations.