The program MONSTR-2.2 is able to deal simultaneously with complex 3-Dimensional constructions undergoing distributed pressure action including aerodynamic load. There are user-friendly interfaces between structural and aerodynamic programs, as well as between Preprocessor, PostProcessor and Processor (main computing code) in each program. The Preprocessor helps to draw new or input existing drawings of construction details (plane cutting patterns) and to generate suitable finite-element mesh. In case of very complex shell, its model can be created using powerful modern CAD/CAM systems (ex. AutoCAD, 3D-Studio), imported into MONSTR and then transformed into ready-to-use finite element system due to special interface. Thus, MONSTR gains access to many CAD procedures applicable when modifying 3D structures: lofting, moving, rotating, scaling, beveling, skewing, bending, tapering, Boolean solid & mesh operations (intersection, subtraction, union), etc. And vice-versa, any created sketch or finite element system can be exported by Preprocessor into CAD software.