About model and data exchange with 3rd party solutions: Revit, Solibri, dRofus, Bluebeam, structural analysis solutions, and IFC, BCF and DXF/DWG-based exchange, etc.
I tried to contact Cigraph to ask about our clients who upgraded from AC9 to AC10 do they have to pay 15 Euro for ArchiStair update? and how can they do that? Is it through CreditCard and the internet?