Thanks, that was exactly the problem - I must have hit the button accidentally before Saving. Thank you very much and I apologize for the silly question

<t>Hi, <br/>
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firstly: thanks for this software and all the great features. I really enjoy working with it. <br/>
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I have planned a little house with it and am almost finished with the exterior walls. But after my last save I am no longer able to select the walls - I can select every other ...