I upgraded a Mac box from 2.8 to 2.8.1 and it still worked.
However, I also found this:
http://www.mono-project.com/Roadmap"""
Unsupported technologiesSome of the .NET technologies have been either deprecated, are too Windows-specific or are very large efforts and our community is unable to produce viable implementations for them.
If someone cares deeply about these APIs and implements them, we would likely bundle them with Mono, but they are not actively being worked on. There might be some code for these on our SVN repository, but the code is not suitable for production use nor do we recommend that developers building cross platform applications depend on it.
...
System.EnterpriseServices
"""
I'm guessing they don't have a Windows-based implementation for that API so they don't ship it. I'll accept patches to the installer to work around that, but don't have time to work on it myself right now.
Keep in mind that Cobra itself is pure .NET bytecode so you shouldn't have issues building it with Mono vs. Windows and then using it on the other. If you do, let me know.
I've even taken OpenGL programs and libs built on Mac and run them on Windows without mods.