I would use Hoffman’s installer
https://github.com/hofmand/video-codec-installers
That will install the original 32 bit version and not the multi thread or the CNESP hacked version of Huffy.
With the command prompt part you change directory (cd ) to where you downloaded the msi. You can hold shift and right click on the spot where your msi. is downloaded and that well give an option to open command prompt there and that is the location you would type in but it would be into a command prompt with admin privelages.
If you have already installed the CNESP version then you have to delete it first by
Delete
HUFFYUV.INF in C:\Windows\INF if existing
Delete
HUFFYUV.DLL in C:\Windows\System32 if existing
Delete HUFFYUV.DLL in C:\Windows\SysWOW64 if existing
In a administrator command window (i.e. CMD), run HuffYUV_x86_v2_1_1.msi and HuffYUV_x64_v2_1_1.msi
Here’s some pics to make it easier.