How to display the master TOC when using Context help in a merged document

I use Robohelp 10. I have created a large Merged Webhelp project and I have set out the project master with nothing in it other than merged projects place markers.

This is the layout of the generated projects etc.

Generate

          Master.htm

               Redirect.htm  (Home page is a redirect to Project 1 Home Page - not in TOC)

mergedProjects

          Project1

              Home Page.htm

          Project2

               Redirect.htm  (Home page is a redirect to Project 1 Home Page - not in TOC)

          Project3 etc.

                Redirect.htm  (Home page is a redirect to Project 1 Home Page - not in TOC)

I can get the help to work great when I call up the master page, which shows the TOC for the whole project and the default home page. And from the breadcrumb the home link goes to the home page and shows the Main TOC

However when I call a page using context help ID I get a single frame with the selected page. The link to show the TOC shows the TOC but it is the top of the merged project and not the master TOC. The home link in the does display the home page but again the displayed TOC is the one of the current merged project.

The question is :

How can I get the Master TOC to show all the time regardless of what page I call using a context ID or how can I create a link that will take me back to the Master TOC?

I remember when I created a previous help file for chm output I had to modify all the ali files in order for the redirect to work throught the master chm. Surely this is not the case with webhelp?

TonyC