If it makes you feel any better, I had the same problem, and your solution (TinyDuino baud at 9600, desktop terminal baud at 57600) worked for me too.  I'd like to know why also!

--Tony

I said I was going to try threading my own rod in my post on Jan. 20, above.  Since then, I received the die and the brass rod, and gave it a go.  While I have threaded many things over the years, I failed at this one.  I could not get the thread to catch in the die and feed the rod forward.  I think it was because the metal was too soft, and the tiny beginning threads torn off rather than helping to feed the die further down the rod.  I haven't given up yet.  I intend to try again.  I think it would go better with an appropriate gauge steel rod instead of brass.  I'll have to look for a source for that.

--Tony

I just bought some female headers from Digikey (part #A115164-ND) and soldered them to the Proto1 board.  Sounds like just what you want.  The pins are pretty close for soldering, but I managed.  I also bought some male headers that match, Digikey part #952-2278-ND.

--Tony

I really like the idea of a sideways extender so a second stack can be built.  Another company sells these for full size Arduinos: http://www.liquidware.com/shop/show/DWX/DoubleWide+ExtenderShield.  They also sell a triple-wide extender.

--Tony

I also am interested in longer screws.  After measuring the diameter of the provided screws, 0.046", I believe they are the standard 00-90 thread size.  I could not find any online that were longer than 1/2".  A couple of places had threaded rod in that thread size, but their prices were too high for a hobbyist, in my opinion.  I was hoping that the next size up would fit, i.e., 0-80, but they are 0.06" in diameter, and the hole I measured was only 0.058"; "close but no cigar".  If anyone finds a source for longer 00-90 screws, please share.

In the meantime, I'm going to try making my own threaded rod.  Micro Mark and some hobby stores sell 3/64" brass rod, as another poster mentioned, which is 0.047".  I ordered some from Micro Mark, along with a 00-90 die to cut the threads.  This is not cost effective, since the die is over $20, but I'm doing it anyway.  I'll just add the die to my collection of other sizes.  I've never cut a thread this fine before.  Wish me luck.

--Tony