Was the curtain wall amended in any way?
If it was it may affect the nodes that the dimensions were attached to.
If the nodes are changed/moved or deleted then the dimensions will do the same.
Curtain walls are basically objects and I know if you dimension a hotspot in an object then the dimension will disappear if that object is amended and that hotspot gets a new ID number.
The dimensions are associated with the hotspot ID number (that the user can't see) and any change to that ID will result in a change (deletion) of the dimension.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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