I've just done my first assessment of a home with ecodesigner. I used my own house so I could compare the result with my actual bills to see how accurate it was. I have customised the materials XML file with more accurate figures also. The dollar value I got for running costs was about 10% UNDER the actual costs. This may well be an acceptable margin for error in all the averaging and assumptions that must go into the calculations - I don't know. But the thing is it doesn't seem to account for 4 skylights that I have in my vaulted ceiling (they are not highlighted in the model review or listed in the openings window) and the building volume doesn't include the vaulted portion of the main living area even though I have the story level set high enough to cover this. I have ceiling slabs in for the flat ceiling area's and the same composite applied as a roof for my vaulted ceilings with the skylights used from the std AC library (just a flat panel skylight). Any tips?