New to X-Pro - common issues?!

most interesting. 
I would say that it's pretty common to see some dust spots and smudges when you apply extreme curves to an out-of-focus shot of a white wall. I've ran into these issues with different brands over the years, usually when trying to burn in the skies dramatically and other such things. The posterization seems pretty extreme though. I don't know what kind of sharpening and curves adjustment you are applying, can you post more details please. I couldn't achieve that effect with settings I tried.

As for black dots on the sensor - well if you see them on un-altered images and they don't come off with a normal cleaning routine, and it's a new camera - have it exchanged or send it in for cleaning. It's just not right.

below is my attempt to repeat your experiment. There are tons of black dust spot ans blotches showing up but they are invisible in normal shots (I applied a rather extreme curve, almost a vertical line).