The intersection of the fireProofing with the slabs

Hi everyone,
I have a problem with my script. I would like that the fireproofing go around the beam but ends when it intersetcs with the slabs. When two slabs are not at the same level, my script do not work properly. It leaves a gap between a the end of fire proofing and the slab.

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I attach my dyn. file
Fire_proofing_DF.dyn (68.8 KB)