Process control UI commands such as /process/inactivate can't be applied to
Rayleigh scattering due to the space in the default name of G4OpRayleigh
("Rayleigh Scattering"), since the command parser uses spaces to separate
arguments and strips extra arguments.  This can be demonstrated in Example N06.
This is a nuisance.

As a side note, the UI command parser does seem to recognize string constants
delimted by quotation marks, but in that case it passes the quotation marks to
the command as well, so it still doesn't work.

In any case, I would advise getting rid of the space in the process name.
G4OpRayleigh is the only process I could find with a space in its name.