The article discusses the possibility of transferring BIM CAD developments from Autodesk Revit to domestic software: Renga, Nanocad. An example for the transfer of developments is the task of linking adjacent design sections, namely networks and constructs, implemented and fully automated in the Autodesk Revit software package with the help of «hole assignments». The main approaches and techniques of working with geometry in the framework of BIM software are revealed, their pros and cons are noted, and arguments are given in support of a solid-state geometric core. In particular, the mechanism of creating polygons in Renga is studied using the example of a wall model. Examples of taking geometry from different software are shown. In conclusion, the main formats for data exchange between software are described.