Hi Ray.
Ok Ray, you're right, thank you.
(Mike, i'm gonna reset all the preferences in a while)
But as a matter of fact, i did resume my real problem in a false example.
My real problem is that i'm working on a file drawn with VW 12.5.3.
I have to make whole floors to symbols including walls (linked to the layer deltaZ), so i can reference them in other layers and other files. And there's the problem (seen in isometric) : the wall became flat and haven't got anymore a height.
Or sometimes the furnitures will jump vertically up or downward.
You notice this only once you insert the symbol.
I join a file in case you want and got time to take a look.
Kind Regards.