Embedded Python and multiprocessing on Windows?

[Apple]

I've been working on a project involving embedding Python into a Windows application. I've got all of that working fine on the C++ side, but the script side seems to be hitting a dead end with multiprocessing. When my script tries to run the same multiprocessing code that works in a non-embedded environment, the code doesn't appear to be executed at all.

A StackOverflow thread gave me a few ideas to try out, so I gave it a shot with these lines added:

sys.argv = ['C:\\path\\to\\script.py']
mp.set_executable("C:\\Python37\\python.exe")
p = mp.Process(target=somefunction)
p.start()

Still no joy. However, a Python.exe window does pop up for a tenth of a second, so *something* is happening.

So does multiprocessing actually work in embedded Python, or am I at a dead end here? My guess is that it's probably linked to Windows not having fork, so the combination of being embedded and having to spawn is making things go goofy.