The shortcut I use in my start menu/desktop/etc for opening the help file has a target of:
"C:\Program Files (x86)\ProMash\winhlp32.exe" "C:\Program Files (x86)\ProMash\PROMASH.HLP"
Works well for me on Win8.1
Does this open the files internally while in ProMash or through win32hlp.exe?
No, it won't open the help file correctly from within promash. I do, however, have a separate 'launcher' in my start menu for ProMash Help that opens correctly.
I recall playing with ways to get the help file to open with win32hlp directly from within ProMash but never succeeded.
A PDF is a reasonable alternative to having to find a (essentially, pirated) version on win32hlp.exe from some poor soul on the internet
. As long as it's quickly and easily navigable then it would be a good alternative. IMO