Thank you for the feedback and sorry for the inconvenience!
As you already know, JustCode doesn't support F# project, thus it is impossible to it to resolve types declared in F# source code. Currently, our team is focused on rebuilding JustCode for VisualStudio 2015 using Roslyn API (we have already released several vesions of it, you can give it a try) and that's why I can't commit that this issue will be resolved any time soon. Also, because of we are using Roslyn to parse the syntax and provide us with the necessary semantic information, there will be no more Good-Code-Reds/Yellows, hence there will be no more false-errors when you reference F# projects, too.
I could suggest you to refer not the F# projects but the their output assemblies instead, while you are working on C#. This way our analyzer will be able to obtain type information from IL, and when you are done roll back the references to the projects. I understand this is pretty inconvenient and annoying but it's the only workaround I can offer you right now.
Once again, excuse us for the caused inconvenience!
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