In the solution i'm currently working, methods of some Forms are accessed static (Classname.Methodname). R# flags this as error "Cannot access non-shared sub 'Show' in shared context". In VB there is always a default instance of a form which can be accessed in that way, so the code is valid.
Another annoying code analysis problem is, that some implicit conversions are marked as errors. The solution i'm working on does heavy Interop with Excel. Each time when a value is assigned to an Excel-property the error "Cannot convert 'xxx' to ???", for example