Culprit Identified

So as I mentioned before I had encountered two big problems with my machine.  #1 was that it appeared to fail miserably when I tried to print a circular object with it.  After doing that once and seeing the result I was a little discouraged and decided to stick with square objects for the time being.  #2 was the fact that the extruder speed was not being controlled by the software due to some kind of communication/firmware error.

#1  After going around the machine tightening up various bolts and greasing up the guide rods and leadscrews I found what was causing the circles to fail to badly.  One of the Z axis posts had slipped out of its bearing hole at the top of the machine due to a loose bolt.  This meant that as the Z axis turned, the table was actually moving back and forth as this free leadscrew twirled about.  I tightened it up and suddenly printing circles was a piece of cake!  

#2  The problems with the extruder speed control ended up being a corrupt firmware file that I had.  I never found the actual problem, I just replaced some of the code with backed up versions and suddenly everything started working.  I assume I just made one too many changes somewhere and screwed everything up.  

So, I now had variable speed and the ability to print pretty accurate arcs and circles!  So I revisited the minimug test print and the result was much better than before!

Mid-print

Finished print before getting cleaned up