The answer to this problem in this post
https://community.graphisoft.com/t5/Libraries-objects/AC27-Accessories-add-on-has-lost-its-connection-to-building/m-p/598624#M45034
Hi,Here is another formula possibility using the floor number directly
Sorry formula in French IFS ( {Property:Paramètres généraux/Numéro
d'étage d'implantation} = 0; "B2"; {Property:Paramètres généraux/Numéro
d'étage d'implantation} = 1; "B1"; {Prop...