You got in a few minutes before me :)
I'd just upgraded to 1.34b and noticed the same issue - all the coverage dots were showing black, as 'no tests are covering this code'. I checked the NCrunch Tests panel, and noticed that many of my specifications were showing as failing, however the individual assertions within that spec all passed. The error in the test panel was saying 'Assembly not found' for the specification constructor. I opened up the Configuration panel and turned 'CopyReferencedAssembliesToWorkspace' to True, and that seemed to fix the issue - now in the Tests panel, all the specifications were showing as passing along with the individual assertions. However, the coverage dots still stayed black.
At this point I purposefully introduced an error in the code to cause failing tests. NCrunch happily reported all tests passing. Yet when I ran the MSpec tests via ReSharper, it reported numerous test failures.
I've rolled back to 1.33b and this functionality is all working as expected - tests that should be failing, are. I'm seeing proper coverage dots now. And I'm also able to turn off 'CopyReferencedAssembliesToWorkspace' and still have full functionality.
I'm pretty busy at the moment but I'll try and replicate this later and submit a bug report.
I am using MSpec 0.4.21.0