Add prebuilt window and doors bucks as you go and dowel into bales. Bales extend up to barges on gable walls. Tie bales into wood frame with galvanized wire. Rebar through the inside of the bales is not required. Install steel roofing on entry.
Windows are flush with exterior wall to reduce the possibility of moisture damage.
Stucco exterior of bales and around bathtub with 2 or 3 coats of cement stucco. Non-bearing interior walls can rest on sandbag foundations. Frame door openings so doors can be added at some later date. Install railing and ladder. Add poly on bottom of top chords trusses to prevent insulation from blocking attic ventilation.