Is there any particular trick to getting DllImport to work?

In my continuing quest to "test all the things" I have set up a managed C++ class library/dll which is being called from a C# Unit-test project. The test code looks a bit like this....

    public static class    Caller
    {
        [DllImport("lib.dll")]
        static extern void codeToTest();
    } 

    [TestClass]
    public class UnitTest1
    {
        [TestMethod]
        public void TestMethod1()
        {
            Caller.codeToTest();
            ...
        }
    }

There is a project dependency between the C++ library and the test project.

Ncrunch is quite happy to build both projects and recognises that the test needs to be re-run if I touch the C++ code. However, it throws an exception saying it can't find the DLL when it tries to run the test...

System.DllNotFoundException: Unable to load DLL 'lib.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)

The DLL _is_ being copied to the unit-test bin/debug folder by the normal build process and if I debug the test using vs/Resharper, they correctly load the DLL.

Is there some special bit of configuration I need to apply to get NCrunch to copy the DLL to its test environment? I'm not sure what's confusing NCrunch here - maybe the fact that folder conventions are different for a C++ project? In this case the lib project outputs to lib\debug\lib.dll rather than lib\bin\debug\lib.dll ?

Thanks for any insight... :-)

Just answering my own question....

Setting "Pre-load all assembly references into test environment" to TRUE seems to have resolved this.