Hotlinked Modules (HLM) can definitely save a great deal of time in your situation.
These Help pages - and links from them - should get you started:
http://helpcenter.graphisoft.com/guides/archicad-20/archicad-20-reference-guide/collaboration/hotlin...
http://helpcenter.graphisoft.com/guides/archicad-20/collaboration-guide-for-archicad-20/collaboratio...
http://helpcenter.graphisoft.com/guides/archicad-17-guides/archicad-17-int-reference-guide/archicad-...
The placed module behaves somewhat like a group that cannot have grouping suspended. On selection, you'll see hollow squares vs a group's hollow circles to let you know you've selected part of an HLM. Ideally, create a meaningful 'master layer' for your placed modules (e.g., don't use the ArchiCAD layer as the master layer). While the module content will respond to layer visibility like normal elements - it is often useful to turn the module master layer on/off to completely hide the HLMs. (As an example, this master layer control can be used to switch the visibility of a different unit design.)
It is also best to keep your attributes (layers, materials, fill types, etc) matched between your main project file and the file that your modules come from. Sometimes this can be a real challenge. For simple projects, it is possible to link the PLN file back to itself, or publish MOD files from PLN file views, to avoid the complexity of keeping attributes in sync across multiple PLN files.
Create a fake project just to play with the concept and see how HLMs work. It seems complex, but is really pretty easy and a great way to model repetitive elements once and yet be able to edit all instances at once.
One of the forum moderators
AC 28 USA and earlier • macOS Sequoia 15.2, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB
