To clarify just a bit...
Event Scheduler v1.2.0 dates back to 2-Series, before 10 program slots were available.
So for 2-Series \\NVRAM\\scheduler.dat in SIMPL simply refers to \NVRAM\Scheduler.dat.
However, 3-Series/4-Series NVRAM folder is separated by Program Slot subfolders.
So \\NVRAM\\scheduler.dat in SIMPL now actually refers to \NVRAM\ProgIDTag\scheduler.dat.
(ProgIDTag is arbitrary, but must match what you set in SIMPL under "Project > Edit Program Header > Program ID Tag")