Vented Cavity Roof - Results Error

Hi I’m trying to model an opaque vented cavity roof as in the file attached and noticed that changing the “stack discharge coefficient”, “wind coefficient” and “effective area” does not seem to produce much difference in the cooling loads

Also when comparing the cooling loads from no cavity, non-vented and vented cavity, the vented cavity seems to be much more effective in a colder place like Amsterdam than in a warmer place like Abu Dhabi. Does this feel correct? What am I doing wrong?
Thanks !!!

Opaque Double Skin (938.7 KB)