Safety and local authority building control regulations will dictate that you must have a structural calculations for your home, whatever the construction material. What's special about this system?
Apart from local regulations, you want to be satisfied as to whether your load bearing walls can hold the whole structure. Especially when you live in an area, where you are subject to earthquakes, floods and storms etc.
Additional possible loadings (e.g. snow in winter on a roof) or circumstances will require you to introduce additional reinforcement to the concrete. This can only be designed by a professional Structural Engineer.
The structural calculation of walls made from ICF/PIF/StyroStones is a simple task for any suitably qualified structural engineer. In reality the system is only a lost shutter for the concrete The physical laws have been known for more than 2.000 years , after all the Colosseum in Rome is made from concrete! Local authority building regulations will take into consideration all relevant circumstances such as earthquakes etc.