After diagnosis and evaluation by the LBS wrencher, I thought I would bring anybody who cares up to speed on the true cause of the above-mentioned ailments:

drive train incompatibilities.

The Truvativ compact crankset on the Nova was billed as 9/10 speed compatible, but as I found out, was not in fact compatible with the 105 10 spd gruppo. I don't know exactly what was incompatible--perhaps some of the spacing and ramping in the chainrings, as the chain consistently fell off at a specific spot in the pedal cycle. Both Truvativ and Jamis apparently were aware of the issue prior to the shop getting in touch with them; Truvativ is sending a replacement crankset, but I will have to wait *another* 1-2 months. Crazy that I got this bike in Jan. and have only ridden it maybe 10 times.

I didn't think that mixing/matching component sets would make that much of a difference, but I guess when you are dealing with the smaller tolerances of the 10-speed world, little things matter.

I'm appreciating my beater fixie more and more.