The ism file based iTwin using iTwin analytical synchronizer continues to be a free product.The second machine is using iTwin Analytical Synchronizer and has no recourse to STAAD. It's FREE to be downloaded.ISM Revit Plugin also free and to be downloaded from https://softwaredownloads.bentley.com/en/ProductDetails/1858?packageid=32361and https://softwaredownloads.bentley.com/en/ProductDetails/1963?packageid=26819 respectively.