I will post here a problem that was already described earlier and related to installing the import plugin on Archicad 25. The problem is described here "No supported Archicad version has been found". Also in this post, tech support tried to solve it in a very strange way, which also does not work. I think that the problem is solved by editing the Archicad 25 registry, or by improving the plugin itself. In general, I tried several different builds of archicad 25, but this plugin did not install on any of them. I always got this error "No supported Archicad version has been found". This happened until I installed Archicad 26. After that, I tried to install UnrealDatasmithArchicadExporter_5_2 and lo and behold! The import plugin found not only version 26, but also version 25 of the archicad! Also, I remembered that when I deleted the plugin for archicad 25, the plugin for archicad 25 was also deleted)). I think that the developers need to pay attention to this problem!