If the insulated envelope values that you have entered are correct, then
I would suspect that both the outside ventilation air that is entering
the building through control and air leakage are to low and that likely
the internal heat gains from equipment from computers, etc. are too low.
The fact that the actual use is higher in both the winter and summer
would indicate the outside air, but I think if you just increase only
the outside air and not the internal electrical use numbers also, then
you'll likely see too big of peak in both the summer and winter. Good
luck, it is also fun trying to match an actual energy use pattern on an
existing building.

Thanks,
David A. Bastow