Modeling different floor 1 than floors 2-6 - Best approach!

I’m trying to model a 6-story building using OpenStudio (3.5.1), OpenStudioApplication (1.5.0), and Sketchup (2023).

I imported floor plan 1 and used it to create the floor plan for floor 1 in Sketchup. I then used Create Spaces from Diagrams, then grouped and hid as Level 1. Did the same for floor 2, and used Create Spaces from Diagrams to create floors 2-6.

I raised floors 2-6 to the height of floor 1, and when done, the measurements I used didn’t line up perfectly. Floors 2-6 are about 1.5" off in some spaces and in others, I’m spot on. The trouble is floor 1 thermal zones don’t show. The whole floor is white.

I don’t think my approach was the right approach.

What’s a better approach?

Some of the spaces on the second floor were probably not at the same level.
Try to check the lower level of them.
Try drawing a surface from one corner (in the wrong spaces) to another (on the right ones) and see if the edges are horizontal.