Item Selector Error

Hello, I’m a new user of Rhino. I want to simulate a natural ventilation on an office building. At the first stages, I created the building model divided into spaces with closed polysurfcaes.
But when i want to use inside grashopper the HB Instersect solids output connect to an item selector, and than a HB room from Solid, than i could make different level with different space data, the program show an error.

Thank you in advice for your help.