Ok I have a solution to this problem now.

Expand WindowsTH-KB2693643-x64.msu by using the following command:

WUSA WindowsTH-KB2693643-x64.msu /extract:<destination>

Then from an elevated command prompt run the following command where the extracted files are located:

pkgmgr /ip /m:<locationoffiles>\WindowsTH-KB2693643-x64.cab for example

pkgmgr /ip /m:c:\temp\rsat\WindowsTH-KB2693643-x64.cab

Wait for a few minutes then this will pop up:

Restart your PC and your right to go. Tools should be installed now and working.

Cheers

Damon