About model and data exchange with 3rd party solutions: Revit, Solibri, dRofus, Bluebeam, structural analysis solutions, and IFC, BCF and DXF/DWG-based exchange, etc.
recently I had a request of someone who wanted to ask if they can modify or actually do some changes and 3-d enhancements in this program (Lightwave with *.lwo format.) is this possible to import an archicad model or save to this format?
Actually the AC export capabilities are pretty good. There is special script for 3dsmax that can automate import models from Archicad process.
You can find it (with some other very useful scripts) over here: http://plugins.angstraum.at/