Hi, this is probably common knowledge, but I just spent a couple hours playing with this and was not able to find an online solution.
To be clear, my issue was using the wall option on the opening section of the Architecture Ribbon, I was not able to see dashed lines at the soffit above the opening, while in plan. The best workaround I found online was to use a component opening, or draw and align model lines.
On a whim, before trying a workaround, I went to the modify ribbon, selected linework in the view tab, changed the line style to hidden, and selected the invisible edge of the opening. It worked.
Again, this is probably such common knowledge that no one thought to write about it, but I am very new to the software. If someone else new runs through a similar search effort to what I just did, hopefully this will help.
Thanks
By default, you cannot see lines of wall above the cut plane.
Option 1: what you already did.
Option 2: create a family under Door category, with nothing except for an Opening Cut, and two symbolic lines locked to the edges of the wall. Use Hidden, or create Overhead Object style and assign it to the lines.
Option 3: basically the in-place version of option 2, see screencast in a few minutes
Very cool, thanks for the screencast, pretty much all of that was new to me. I need an entire library of those to watch if you have on handy...
What I like about the way I did it, is that I can stretch the wall opening with grips in real time.