OR use the "normal way": Elements that should not link each other needs to stay on layers with a different "intersection group number" (the number you see next to the layer name, in the Layer setting window).
Every element, in ArchiCAD can "merge" only with other elements with the SAME intersection number.
The intersection number 0 (zero) is a special one. Elements in layers with this number are NEVER linked to others (not with other layers with zero, nor in the same layer).
Not sure to be clear, but do a try... or read this topic on the user manual
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--Roberto Corona--
www.archiradar.com
AC18 - ITA full on Win10
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