Archicad 18 Library Download !!better!! Link
When you open an old file in ArchiCAD 18, it should ask you to "Migrate ArchiCAD Libraries". This automatically replaces old objects with their version 18 equivalents.
The object exists but the macro (sub-component) is missing. archicad 18 library download
Move the entire library to your local SSD. Network libraries with older GDL objects cause severe lag in ArchiCAD 18. When you open an old file in ArchiCAD