You could draw both stages in seperate .plns and hotlink them together in one 'master' .pln. Make two dedicated module layers like 'stage 1 module' and 'stage 2 module'. You can then create your layer combo's to include or exclude that layer. The layer of the module functions sort of like on/off switch. You might have some issues with layer intersection priorities this way. I recall having issues with that. Stuff intersecting that wasn't supposed to intersect.
This is the method with the least amount of work involved. Personally I make 'module export' layer combinations in my seperate .plns and marque my model and save a .mod file, because linking .plns also links all the sections, elevations, unwanted layers etc. I like a tidy 'master' file.
We use this setup a lot with 'large' scale residential projects, with several different buildings linked into a masterplan.
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
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