Intellisense don’t work in C++/CLI/Mixed mode project from VS2010… by design Redmond? Check.. this article on Microsoft Connect http://tinyurl.com/34qrz4s
You can try Visual Assist X from Whole Tomato Software it solves the problem and reintroduce the intellisense in mixed mode projects. Download here.

If you rename a resx inside Visual Studio and rebuild.. creating a new assembly. The resource name is still the same as before. BUT if you delete the solution .ncb file and rebuild again THEN the resx/resource have the new name in the assembly! Check using Red Gate Reflector. This is tested and verified on Visual Studio 20005 sp1.