MegaM@Rt2 is a large European project dedicated to the provisioning of a model-based methodology and supporting tooling for system engineering at a wide scale. It notably targets the continuous development and runtime validation of such complex systems by developing the MegaM@Rt2 framework to address a large set of engineering processes and application domains. This collaborative project involves 27 partners from 6 different countries, 9 industrial case studies as well as over 30 different tools from project partners (and others). In the context of the project, we opted for a pragmatic model-driven approach in order to specify the case study requirements, design the high-level architecture of the MegaM@Rt2 framework, perform the gap analysis between the industrial needs and current state-of-the-art, and to plan a first framework development roadmap accordingly. The present paper concentrates on the concrete examples of the tooling approach for building the framework architecture. In particular, we discuss the collaborative modeling, requirements definition tooling, approach for components modeling, traceability and document generation. The paper also provides a brief discussion of the practical lessons we have learned from it so far.