I'm having a recurring issue with Resharper marking valid StaticResource declarations as errors. It's not an issue of finding the resource in question, it can't seem to find the ResourceKey property itself - but only when I decare it in its expanded mode - without the curly braces.
Here is an example - I composed an image as a sequence of me hovering over the three elements in the tag (in the last one I'm hovering over "PageStyle") - you can see where it shows an error. This isn't a show stopper because everything works as it should, but it makes the Solution-wide analysis completely useless, it's just filled up with all of the "Could not resolve symbol 'ResourceKey' errors.
The errors can be "ignored" in error view - but as soon as xaml is edited somewhere (like Expression Blend), they all reappear.
Using Silverlight 4, VS 2010 SP1, and latest version of Resharper - but this problem has been with me for a long time now, though solution-wide analysis became very useful for me lately so this became much more irritating all of a sudden.