One of the benefits of "VX" releases is they can run side-by-side. This means there is no longer a requirement to "switch" releases like there was with PADS 9.5 and earlier. Both PADS VX.0 and PADS VX.1 releases can co-exist in the Start Menu*, and you can even run programs from both versions at the same time!
The only time you might want to run the Release Switcher is to:
Set the "active" release for the purpose of file associations (for Ex: when you double-click a .pcb which release of PADS Layout does it open), and
Do what the Configurator used to do at pre-VX releases - reregister DLLs, define WDIR, recreate Start Menu shortcuts, and run other similar tasks in the event of an application crash or other unexpected behavior.
For more details on the 'Release Switcher' refer to TechNote MG586150 on SupportNet.
* Start Menu locations for PADS VX.0 and PADS VX.1:
Start Menu > Mentor Graphics PCB > PADS VX.0 (32-bit)