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Hi @camille.bobeau ,

Everything works fine with the instructions from blogpost you mentioned.

>>>>>the command "shift+spacebar" seems to try to do some 3D stuff

3D Orbit turns on when you hold Shift key and keep Spacebar pressed for a long time.

>>>>>The symbol saying 2 objects are overlapping is showing, but there is no dialog box to choose from one another.

There is no dialog box in AutoCAD for Mac, as soon as you enter selection cycling mode.

You can try another method:

1/ Ensure that you have all system variables set:

- selectionpreview to 3

- selectioncycling to 1 or 2

- legacyctrlpick to 2

2/ Now

a/  Outside command: when you need to preselect overlapping object, you can pick on objects with Shift key pressed - you will see object highlighted, continue to pick with mouse on objects, they will be highlighted in turn. Once you see the object you need, you hit Return key and get object you need selected.

b/ Inside command: when you need to select overlapping object when AutoCAD asks to select objects, you use method described in blogpost.