I really don't know the solution to your problem.
But has it anything to do with the location of the section line in plan?
I quickly looked at the video and I think it said something about centring the curtain wall to the section.
Maybe the section line is not in exactly the correct location in plan?
Or it could be that the tutorial is for an older version than what you are working in?
There may be some subtle difference between the versions.
Fortunately you should be able to just move the wall in plan to the position it should be.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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