I actually did start with solids (attached). Everything seemed fine at that point.

Now, what what weird was that when I did the lofts (second attached) and connected up the "corners" of the part, that's when the issues arose. Before that point in time, the part behaved as one nice, big manipulatable solid. However, the lofting created those lines intersecting the insides of the large semicircles on either side of the part running diagonally, creating what look like triangles. They were not there on the original model - the lofting created them, as odd as that sounds. At that point, the part became unprintable as per Netfabb, the lofting somehow (I'm surmising) pulling or altering the curves that it was based off of.

The main solid (first attached) passed Netfabb and Shapeways before the lofting was attempted. Interestingly, its only when the lofting takes place that the main solid (really, the semicircles and triangular regions) become "stressed" and unprintable, hence my desire to just make the entire thing a solid.

I eliminated those little areas you pointed out on my original attachment to clear things up for clarity.

Thanks for any ideas,

Bob