I have fixed this issue now and I think thats it. I am now happy with the Hyperlink implementation.

This changeset fixes that and another issue. I discovered that Word allows Hyperlinks to be defined in two ways, inline and normal. DocX now supports both.
This changeset also contains new unit tests that will hopefully prevent Hyperlink support from braking again.

Fixed a bug with DocX ignoring the CAPS Element.

Added a new unit test to test ReplaceText, based on ReplaceTests.docx
The Test fails.  This functionality worked in the previous release.

Removed the strong name key as per Cathal's suggestion.

Big thanks to np83 not only for finding this bug but also posting a fix and unit tests.

This projects contains many of the examples upload on my blog.
Each time docx is released, I will update these examples so as they still work regardless of API changes.

2) Gave UnitTests internal access to DocX.dll 
DocX AssemblyInfo.cs
[assembly: InternalsVisibleTo("UnitTests")]

3) Updated target framework to .NET 4.0.

4) Fixed bug with InsertText() Formatting object was set to null by default, should have been new Formatting()

// Create a new document.
using (DocX document = DocX.Create(@"C:\Users\Cathal\Desktop\Hello.docx"))
{
    // Set this documents orientation to landscape and save.
    document.PageLayout.Orientation = Orientation.Landscape;
    document.SaveAs(@"Landscape.docx");

    // Set this documents orientation to portrait and save.
    document.PageLayout.Orientation = Orientation.Portrait;
    document.SaveAs(@"Portrait.docx");
}

Added bug fix for RemoveText when index is greater than possible.
Removed a few function overloads by utilising .NET 4.0 optional parameters.

Added unit tests for Paragraph.RemoveHyperlink(int index)

    runLookup
    BuildRunLookup();

Added new unit tests for Paragraph.InsertHyperlink()

Added getter and setter of document core properties for DocX.
Added unit test for ApplyTemplate.