Get the Check Duplicates goodie/addon to get rid of duplicate lines, because that many lines can't be right.
The addon can be installed from: help > archicad downloads
You can also try selecting lines, circles, polylines and using Linework Consolidation tool. I would divide this up into several takes, as doing that many at once, will most likely take forever or make ArchiCAD lock up.
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
Windows 10 Pro
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