Wind Surface Loads Bypassing Interior diaphragms

It is my understanding that wind loads in RAM Frame are distributed vertically between each diaphragm. However, I have a multistory structure that is encased with a curtain wall between the ground floor and roof that distributes wind load vertically from the first floor diaphragm to steel wind girts and then up to the roof diaphragm. The wind girts do not have a diaphragm associated with their level. Within this curtain wall box is a large ramp system composed of 6 levels of diaphragms that will not be exposed to any wind load.

When I run RAM generated wind loads, the loads distribute from the first floor diaphragm to the first ramp landing diaphragm, then subsequently between each ramp diaphragm rather than to the exterior wind girts. When I apply user defined wind loads, I am unable to apply a load to the wind girts because there is no diaphragm associated with them, so the wind load path does not apply bending to the wind girts and columns accurately.

Is there a way to apply a wind surface load that distributes vertically to simulate the curtain wall applying force to the wind girts without modeling a lateral wall system?