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Log Construction questions

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I'm assisting another architect on a log home (duplex, actually) and need to ask a few questions.
1) Information on engineering for lateral wall strength.  Are there any quantifiable info sources or data on how much the notched joinery can withstand?  I've found some 'log building standards' at:
.. that gives some basic 'rules of thumb' - but I would like more (and don't really see anything like this within).
I notice recommendations about distance between windows, doors, etc (below which the wall is weakened - understandably).
2) Wouldn't it make sense to utilize some of the interior walls as shear walls to 'beef up' these exterior log walls -- (even simply utilizing 45° 1x diagonal sheathing - exposed, on both sides of intersecting walls - as a design element on those walls framing into the exterior walls).  We have a common wall separating the duplex units - to be log construction - and, by notching this connection, will gain some strength here.  Other than that, the structure is basically rectangular (40' x 70') with no other 'natural' intersections to build strength along the eave walls.
The roof is framed with standard 2x lumber trusses - so thrust loads from roof framing is taken care of thru the truss.
3) I am finding settlement and shrinkage issues (see above 'standards') talking about 6% settlement of the logs over the initial (5) years.  That translates into something approximating 6" over the 8' (+-) wall height.  I'm not particularly concerned with detailing (particularly interior partitions) to handle this - but are these numbers rational?  I'm not doubting it at all - but just need a broader perspective here.  We're talking 'green' logs (at least, that's what the owner has mentioned - he's planning on setting up a planing mill to do his log machining).  Log profiles are basically rectangular (out of 8x8 actual cross section) with radiused exterior face and tongue and groove interconnections (3/4"x1") - log-to-log.  Would kiln-dried stock be better?  According to the standards above, it doesn't hardly matter.
4) Connections between log-to-log: I assume any of several mechanical connections are workable - pegs, spikes, lag bolts, etc - but I can't find any real recommendations on spacing / angling, etc.  It would seem some good 12" or so spikes every few feet or so would work - but am I overlooking something?
Any of you fine folks out here got some extensive log building experience that you could pass along?
-- john.