How to replace Navigator and WindowUtil methods in 4.5 API?

Could some kind soul please tell me how to replace the following Resharper plugin API methods which I had working fine under 4.1 so that I may hopefully get it running again under 4.5...

(1) WindowUtil.ShowInfoMessage and WindowUtil.ShowYesNoMessage

(2) Navigator.NavigateDeclaredElement
I need this because given an ITypeElement I want to jump to a method which starts with a value - this code extract works under 4.1:

                IList<IMethod> methods = typeElement.Methods;
                foreach (IMethod method in methods)
                {
                    if (method.ShortName.StartsWith(partialMethodName))
                    {
                        // Want to navigate to this method.
                        Navigator.NavigateDeclaredElement(method, true);
                        return;
                    };
                }


FYI My plug-in gives me "Goto Test" functionality via a context menu in the IDE. If you are in a class "Foo" in method "Bar" and choose my Goto Test menu option, it will look for a "FooTest" class (using some specific naming conventions I use in my projects) and if not present in the solution create a file in the appropriate project. It will then add a "Bar" test method stub. Alternatively if "FooTest" existed it would open it up and navigate to the first test method that started with "Bar".

Many thanks for your help.