StartPortableApps.exe is not quite fully portable, it relies on presence and relative position of "PortableApps" directory.
I believe this is true as I have not been able to find out how change the directory name and still use the start exe.
To clarify StartPortableApps.exe can be moved anywhere as long as a directory called "PortableApps" exists in the same directory with the Portable apps menu located inside.
The Portability issue is that you can't use it to point to any other directory other than "PortableApps" and it must be in the same relative location.
All the other apps support changing directory names (including "PortableApps"), usually for program as well as data/profile locations.
