dlbahler, that's great... i think one of my mistakes was thinking that each bent had a beam across the floor parallel to the tie beamm but if it's just the sills then it can easily be handled with a landing and a step down inside the door
studio, i pretty sure i'm working under the same radiant floor plan you've seen installed. i'm not clear on the purpose of the metal stand off, to keep the heat from affecting the timber maybe? the grade is step enough that i'm cutting it back and installing a retaining wall with a back patio as buffer from soil and rain, but a curb is a good suggestion i haven't run across before, which is suprising given that we're looking at using strawbale for cladding and strawbale folks are pretty fearful of any kind of moisture.
i can't tell you all how pleased i am to find this forum, this link alone
http://www.arlingtontimberframes.com/enclosure.htm answered the huge question for me of how to finish the roof.
thanks again!