Excuse us for the caused inconvenience!
The good news is that we've found what is causing this Good-Code-Red - there is a namespace Windows.Foundation.Diagnostics in mscorlib targeting .NET4.5(.1), so when JustCode is analyzing the whole type name "Windows.Forms...", JustCode's analyzer is picking the mentioned namespace first since its fully qualified name starts with 'Windows' rather than 'System' and therefore it can not resolve the correct type.
The bad news is that the fix will be time and resources consuming because there is a big infrastructure that is dealing with the namespace/type/member resolution, so each change might result in generating new false errors.
I will raise the priority of this bug, so you can expect it in some future release.
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