Ah. Thanks Lazlo! Yes it's invalid but I had no idea the purple colour indicated that. Is it for stairs only?
No, it is for other elements that can link to the storey level as well.
Such as walls where you can link the top of the wall to a storey level.
It is then possible to adjust the storey height so the top is below the base of the wall (i.e. it was a high bulk-head wall).
The wall will now be that pinky/purple colour.
Actually you can change the colour and turn this option off in the Work Environment >On- Screen Options > Use uniform colour to highlight inverted elements.
One of the forum moderators.
Versions 6.5 to 25
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