Provided the models are saved as a .gsm file you can just put them in a folder you can find from ArchiCAD, open the program and load the parts from the 'File/Libraries and Objects/Library Manager' dialogue. Locate the model parts in the left hand window and add them to the project Library parts in the right hand window.
Once you have them loaded into your project just use the Object Tool to place the object where you want it. Hope this is clear.
Cheers,
Gerald
"The simplification of anything is always sensational" GKC
AC 25-4013 USA, CadImage Tools
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