Natural Ventilation using Butterfly CFD

Hello I am a new user to Butterfly and have done extensive research on the simulation and modelling methodology and still am encountering the following issues :-

a)My simulation ran without any errors without defining a refinement region but i am not able to see any variation in wind flow inside my building model.

b) After defining a refinement region, i got an unexpected result which showed widely varying results from 0 m/s or 2 m/s in the same room.

I used the outdoor airflow example script with a wind velocity of 3.1 mls.

I have tried everything and would appreciate any help from fellow butterfly users . I am unable to upload images and errors to describe my issue as I am a new user.

Anyone know how I can enable that?

Thanks