If there's anyone out there that hasn't gotten their Win32.hlp back up and running under Win10, I ran across this. It includes a patched WinHelp32.exe and install.cmd for a quick and convenient semi-automatic fix. There's a couple of procedures offered up; the first one worked for me right off.
https://appuals.com/how-to-read-hlp-fil ... indows-10/
Bill
Reading .HLP files on Windows 10
Reading .HLP files on Windows 10
PB 5.72 (32-bit) on Win 10.