Hi Jean,
I think you are overlooking that when the dimension string is not parallel to what it is dimensioning, then the option to display the UNIT WIDTH & HEIGHT is intentially voided by the program.
Look at the screenshots you posted, spedifically Step 2 where the wall has been rotated, but the dimension string has not and is no longer parallel to what it is dimensioning. Note that the window width is no longer the unit width, but it is a correct live dimension. When the measured live dimension is no longer equal to the unit width, then the option to also display the unit height is no longer available.
This makes sense to me as if the unit height was displayed, someone reading the drawings might accidentally think the 0,895 is the unit width.
Whether you consider this as a bug or not is debatable. I prefer that the UNIT WIDTH & HEIGHT display is voided because it tells the archicad operator that the dimension string is not parallel to what it is dimensioning. And, as I said above this prevents someone from accidentally noting an incorrect unit width.
But feel free to disagree
Erika
Architect, Consultant
MacBook Pro Retina, 15-inch Yosemite 2.8 GHz Intel Core i7 16 GB 1600 MHz DDR3
Mac OSX 10.11.1
AC5-18
Onuma System
"Implementing Successful Building Information Modeling"