 The apparent incompatibility with Radial Port locations might be explained by the as-yet unstable configuration of the Nodes, being shown as spherical 10-ports modules in some configurations, but cylindrical 3-port modules in others.Many other features of the baseline station configuration of the time also appear quite different from the eventual ISS.As 1990 approached, the size of the CBM had been stabilized by a specific Engineering approach to the design of modules.